1 00:00:07,290 --> 00:00:11,200 chemicals mmm 2 00:00:11,200 --> 00:00:11,210 3 00:00:11,210 --> 00:00:13,820 studies as a matter of 4 00:00:13,820 --> 00:00:13,830 studies as a matter of 5 00:00:13,830 --> 00:00:16,670 studies as a matter of and we said that too 6 00:00:16,670 --> 00:00:16,680 and we said that too 7 00:00:16,680 --> 00:00:19,580 and we said that too chemical reactions transformations of 8 00:00:19,580 --> 00:00:19,590 chemical reactions transformations of 9 00:00:19,590 --> 00:00:21,680 chemical reactions transformations of those energies in one form to the others 10 00:00:21,680 --> 00:00:21,690 those energies in one form to the others 11 00:00:21,690 --> 00:00:25,460 those energies in one form to the others and to what extent a chemical reaction 12 00:00:25,460 --> 00:00:25,470 and to what extent a chemical reaction 13 00:00:25,470 --> 00:00:30,620 and to what extent a chemical reaction will proceed to the direction it's 14 00:00:30,620 --> 00:00:30,630 will proceed to the direction it's 15 00:00:30,630 --> 00:00:32,990 will proceed to the direction it's written actually to the product and all 16 00:00:32,990 --> 00:00:33,000 written actually to the product and all 17 00:00:33,000 --> 00:00:41,960 written actually to the product and all of these are so dynamic subjects and we 18 00:00:41,960 --> 00:00:41,970 of these are so dynamic subjects and we 19 00:00:41,970 --> 00:00:45,500 of these are so dynamic subjects and we also simply define the internal energy 20 00:00:45,500 --> 00:00:45,510 also simply define the internal energy 21 00:00:45,510 --> 00:00:49,520 also simply define the internal energy and enthalpy just refresh our memories 22 00:00:49,520 --> 00:00:49,530 and enthalpy just refresh our memories 23 00:00:49,530 --> 00:00:51,500 and enthalpy just refresh our memories about those because we have covered 24 00:00:51,500 --> 00:00:51,510 about those because we have covered 25 00:00:51,510 --> 00:00:54,860 about those because we have covered those in chapter 5 and the first law of 26 00:00:54,860 --> 00:00:54,870 those in chapter 5 and the first law of 27 00:00:54,870 --> 00:00:58,040 those in chapter 5 and the first law of thermodynamics actually remember which 28 00:00:58,040 --> 00:00:58,050 thermodynamics actually remember which 29 00:00:58,050 --> 00:01:00,380 thermodynamics actually remember which says that the total energy of the 30 00:01:00,380 --> 00:01:00,390 says that the total energy of the 31 00:01:00,390 --> 00:01:03,229 says that the total energy of the universe is constant so you cannot 32 00:01:03,229 --> 00:01:03,239 universe is constant so you cannot 33 00:01:03,239 --> 00:01:06,770 universe is constant so you cannot create energy out of nothing nor you can 34 00:01:06,770 --> 00:01:06,780 create energy out of nothing nor you can 35 00:01:06,780 --> 00:01:09,260 create energy out of nothing nor you can destroy the present energy you can only 36 00:01:09,260 --> 00:01:09,270 destroy the present energy you can only 37 00:01:09,270 --> 00:01:12,950 destroy the present energy you can only just transform one form of energy to 38 00:01:12,950 --> 00:01:12,960 just transform one form of energy to 39 00:01:12,960 --> 00:01:16,490 just transform one form of energy to another form but the total energy of the 40 00:01:16,490 --> 00:01:16,500 another form but the total energy of the 41 00:01:16,500 --> 00:01:19,130 another form but the total energy of the universe is constant that's the first 42 00:01:19,130 --> 00:01:19,140 universe is constant that's the first 43 00:01:19,140 --> 00:01:23,330 universe is constant that's the first law of thermodynamics actually now the 44 00:01:23,330 --> 00:01:23,340 law of thermodynamics actually now the 45 00:01:23,340 --> 00:01:26,600 law of thermodynamics actually now the both we said the enthalpy and the 46 00:01:26,600 --> 00:01:26,610 both we said the enthalpy and the 47 00:01:26,610 --> 00:01:29,149 both we said the enthalpy and the entropy are state functions we also 48 00:01:29,149 --> 00:01:29,159 entropy are state functions we also 49 00:01:29,159 --> 00:01:31,160 entropy are state functions we also refresh our memories about the state 50 00:01:31,160 --> 00:01:31,170 refresh our memories about the state 51 00:01:31,170 --> 00:01:34,190 refresh our memories about the state function remember the change in state 52 00:01:34,190 --> 00:01:34,200 function remember the change in state 53 00:01:34,200 --> 00:01:37,310 function remember the change in state functions only depends on the final and 54 00:01:37,310 --> 00:01:37,320 functions only depends on the final and 55 00:01:37,320 --> 00:01:40,219 functions only depends on the final and initial state not the path followed from 56 00:01:40,219 --> 00:01:40,229 initial state not the path followed from 57 00:01:40,229 --> 00:01:42,350 initial state not the path followed from the initial to the final state as we 58 00:01:42,350 --> 00:01:42,360 the initial to the final state as we 59 00:01:42,360 --> 00:01:46,190 the initial to the final state as we said and both enthalpy and entropy are 60 00:01:46,190 --> 00:01:46,200 said and both enthalpy and entropy are 61 00:01:46,200 --> 00:01:49,609 said and both enthalpy and entropy are state functions on the other side the 62 00:01:49,609 --> 00:01:49,619 state functions on the other side the 63 00:01:49,619 --> 00:01:53,390 state functions on the other side the heat which is represented by Q and work 64 00:01:53,390 --> 00:01:53,400 heat which is represented by Q and work 65 00:01:53,400 --> 00:01:56,090 heat which is represented by Q and work which is represented by W are also 66 00:01:56,090 --> 00:01:56,100 which is represented by W are also 67 00:01:56,100 --> 00:01:59,030 which is represented by W are also thermodynamic terms tenet we use those 68 00:01:59,030 --> 00:01:59,040 thermodynamic terms tenet we use those 69 00:01:59,040 --> 00:02:02,330 thermodynamic terms tenet we use those dynamics functions they are not state 70 00:02:02,330 --> 00:02:02,340 dynamics functions they are not state 71 00:02:02,340 --> 00:02:04,190 dynamics functions they are not state functions that they're not state 72 00:02:04,190 --> 00:02:04,200 functions that they're not state 73 00:02:04,200 --> 00:02:07,730 functions that they're not state functions and again we talked about 74 00:02:07,730 --> 00:02:07,740 functions and again we talked about 75 00:02:07,740 --> 00:02:10,639 functions and again we talked about spent spontaneous process we define what 76 00:02:10,639 --> 00:02:10,649 spent spontaneous process we define what 77 00:02:10,649 --> 00:02:13,069 spent spontaneous process we define what a spontaneous process is remember again 78 00:02:13,069 --> 00:02:13,079 a spontaneous process is remember again 79 00:02:13,079 --> 00:02:15,470 a spontaneous process is remember again if a process is taking place by itself 80 00:02:15,470 --> 00:02:15,480 if a process is taking place by itself 81 00:02:15,480 --> 00:02:18,430 if a process is taking place by itself without any outside assistance or 82 00:02:18,430 --> 00:02:18,440 without any outside assistance or 83 00:02:18,440 --> 00:02:21,370 without any outside assistance or interference that process is called 84 00:02:21,370 --> 00:02:21,380 interference that process is called 85 00:02:21,380 --> 00:02:24,319 interference that process is called spontaneous process spontaneous process 86 00:02:24,319 --> 00:02:24,329 spontaneous process spontaneous process 87 00:02:24,329 --> 00:02:31,869 spontaneous process spontaneous process and we also simply talk about the 88 00:02:31,869 --> 00:02:31,879 and we also simply talk about the 89 00:02:31,879 --> 00:02:35,240 and we also simply talk about the non-spontaneous process and the 90 00:02:35,240 --> 00:02:35,250 non-spontaneous process and the 91 00:02:35,250 --> 00:02:39,830 non-spontaneous process and the reversible processes - but we just 92 00:02:39,830 --> 00:02:39,840 reversible processes - but we just 93 00:02:39,840 --> 00:02:42,229 reversible processes - but we just indicated that the spontaneity of the 94 00:02:42,229 --> 00:02:42,239 indicated that the spontaneity of the 95 00:02:42,239 --> 00:02:46,220 indicated that the spontaneity of the process is also affected by the 96 00:02:46,220 --> 00:02:46,230 process is also affected by the 97 00:02:46,230 --> 00:02:48,800 process is also affected by the temperature of the surrounding 98 00:02:48,800 --> 00:02:48,810 temperature of the surrounding 99 00:02:48,810 --> 00:02:51,380 temperature of the surrounding temperature of the system actually as we 100 00:02:51,380 --> 00:02:51,390 temperature of the system actually as we 101 00:02:51,390 --> 00:02:53,690 temperature of the system actually as we have given example like mountain of ice 102 00:02:53,690 --> 00:02:53,700 have given example like mountain of ice 103 00:02:53,700 --> 00:02:57,319 have given example like mountain of ice above zero is spontaneous but mountain 104 00:02:57,319 --> 00:02:57,329 above zero is spontaneous but mountain 105 00:02:57,329 --> 00:03:00,589 above zero is spontaneous but mountain of ice below zero is not spontaneous is 106 00:03:00,589 --> 00:03:00,599 of ice below zero is not spontaneous is 107 00:03:00,599 --> 00:03:02,300 of ice below zero is not spontaneous is not a spontaneous reaction it doesn't 108 00:03:02,300 --> 00:03:02,310 not a spontaneous reaction it doesn't 109 00:03:02,310 --> 00:03:04,130 not a spontaneous reaction it doesn't take place by itself 110 00:03:04,130 --> 00:03:04,140 take place by itself 111 00:03:04,140 --> 00:03:07,869 take place by itself now we're reversible and irreversible 112 00:03:07,869 --> 00:03:07,879 now we're reversible and irreversible 113 00:03:07,879 --> 00:03:12,140 now we're reversible and irreversible processes again when we say reversible 114 00:03:12,140 --> 00:03:12,150 processes again when we say reversible 115 00:03:12,150 --> 00:03:16,910 processes again when we say reversible process we just mentioned that we have 116 00:03:16,910 --> 00:03:16,920 process we just mentioned that we have 117 00:03:16,920 --> 00:03:20,180 process we just mentioned that we have to remember the equilibrium processes in 118 00:03:20,180 --> 00:03:20,190 to remember the equilibrium processes in 119 00:03:20,190 --> 00:03:23,690 to remember the equilibrium processes in thermodynamics literally means that if 120 00:03:23,690 --> 00:03:23,700 thermodynamics literally means that if 121 00:03:23,700 --> 00:03:27,289 thermodynamics literally means that if you simply change one of the function 122 00:03:27,289 --> 00:03:27,299 you simply change one of the function 123 00:03:27,299 --> 00:03:30,199 you simply change one of the function infinities will amount the process 124 00:03:30,199 --> 00:03:30,209 infinities will amount the process 125 00:03:30,209 --> 00:03:33,110 infinities will amount the process should be reversed but infinitesimal 126 00:03:33,110 --> 00:03:33,120 should be reversed but infinitesimal 127 00:03:33,120 --> 00:03:39,140 should be reversed but infinitesimal amount so for this only the equilibrium 128 00:03:39,140 --> 00:03:39,150 amount so for this only the equilibrium 129 00:03:39,150 --> 00:03:42,140 amount so for this only the equilibrium state is appropriate and when we say 130 00:03:42,140 --> 00:03:42,150 state is appropriate and when we say 131 00:03:42,150 --> 00:03:44,569 state is appropriate and when we say reversible process and thermodynamics we 132 00:03:44,569 --> 00:03:44,579 reversible process and thermodynamics we 133 00:03:44,579 --> 00:03:48,080 reversible process and thermodynamics we mean that it is the equilibrium State 134 00:03:48,080 --> 00:03:48,090 mean that it is the equilibrium State 135 00:03:48,090 --> 00:03:50,780 mean that it is the equilibrium State equilibrium State for example when we 136 00:03:50,780 --> 00:03:50,790 equilibrium State for example when we 137 00:03:50,790 --> 00:03:54,979 equilibrium State for example when we talk about the mountain of ice and if we 138 00:03:54,979 --> 00:03:54,989 talk about the mountain of ice and if we 139 00:03:54,989 --> 00:03:56,710 talk about the mountain of ice and if we talk about the reversible process 140 00:03:56,710 --> 00:03:56,720 talk about the reversible process 141 00:03:56,720 --> 00:03:59,809 talk about the reversible process irreversible mountain of ice to the 142 00:03:59,809 --> 00:03:59,819 irreversible mountain of ice to the 143 00:03:59,819 --> 00:04:02,659 irreversible mountain of ice to the water we mean we have to carry out at 144 00:04:02,659 --> 00:04:02,669 water we mean we have to carry out at 145 00:04:02,669 --> 00:04:06,860 water we mean we have to carry out at the melting point of ice which is zero 146 00:04:06,860 --> 00:04:06,870 the melting point of ice which is zero 147 00:04:06,870 --> 00:04:09,949 the melting point of ice which is zero degrees centigrade or 273 any other 148 00:04:09,949 --> 00:04:09,959 degrees centigrade or 273 any other 149 00:04:09,959 --> 00:04:13,759 degrees centigrade or 273 any other temperatures the mountain of ice will 150 00:04:13,759 --> 00:04:13,769 temperatures the mountain of ice will 151 00:04:13,769 --> 00:04:17,060 temperatures the mountain of ice will not be a reversible process but it will 152 00:04:17,060 --> 00:04:17,070 not be a reversible process but it will 153 00:04:17,070 --> 00:04:19,699 not be a reversible process but it will be irreversible process we also said 154 00:04:19,699 --> 00:04:19,709 be irreversible process we also said 155 00:04:19,709 --> 00:04:22,790 be irreversible process we also said that all spontaneous processes are 156 00:04:22,790 --> 00:04:22,800 that all spontaneous processes are 157 00:04:22,800 --> 00:04:25,969 that all spontaneous processes are irreversible processes or spontaneous 158 00:04:25,969 --> 00:04:25,979 irreversible processes or spontaneous 159 00:04:25,979 --> 00:04:29,469 irreversible processes or spontaneous processes are irreversible processes now 160 00:04:29,469 --> 00:04:29,479 processes are irreversible processes now 161 00:04:29,479 --> 00:04:33,230 processes are irreversible processes now we try to define another state function 162 00:04:33,230 --> 00:04:33,240 we try to define another state function 163 00:04:33,240 --> 00:04:37,760 we try to define another state function entropy again and entropy is a measure 164 00:04:37,760 --> 00:04:37,770 entropy again and entropy is a measure 165 00:04:37,770 --> 00:04:43,219 entropy again and entropy is a measure of randomness of a system or you can say 166 00:04:43,219 --> 00:04:43,229 of randomness of a system or you can say 167 00:04:43,229 --> 00:04:44,150 of randomness of a system or you can say it's MN on the 168 00:04:44,150 --> 00:04:44,160 it's MN on the 169 00:04:44,160 --> 00:04:46,160 it's MN on the other side you can define it as the 170 00:04:46,160 --> 00:04:46,170 other side you can define it as the 171 00:04:46,170 --> 00:04:50,900 other side you can define it as the measure of order now as the order of the 172 00:04:50,900 --> 00:04:50,910 measure of order now as the order of the 173 00:04:50,910 --> 00:04:55,070 measure of order now as the order of the system increases entropy decreases as 174 00:04:55,070 --> 00:04:55,080 system increases entropy decreases as 175 00:04:55,080 --> 00:04:58,330 system increases entropy decreases as the chaos increases entropy increases 176 00:04:58,330 --> 00:04:58,340 the chaos increases entropy increases 177 00:04:58,340 --> 00:05:01,220 the chaos increases entropy increases again as the randomness increases 178 00:05:01,220 --> 00:05:01,230 again as the randomness increases 179 00:05:01,230 --> 00:05:04,130 again as the randomness increases entropy increases randomness decreases 180 00:05:04,130 --> 00:05:04,140 entropy increases randomness decreases 181 00:05:04,140 --> 00:05:07,370 entropy increases randomness decreases entropy decreases that means order means 182 00:05:07,370 --> 00:05:07,380 entropy decreases that means order means 183 00:05:07,380 --> 00:05:11,390 entropy decreases that means order means low entropy and disorder chaos means 184 00:05:11,390 --> 00:05:11,400 low entropy and disorder chaos means 185 00:05:11,400 --> 00:05:13,760 low entropy and disorder chaos means high entropy that's what we have to 186 00:05:13,760 --> 00:05:13,770 high entropy that's what we have to 187 00:05:13,770 --> 00:05:16,310 high entropy that's what we have to always remember in terms of the entropy 188 00:05:16,310 --> 00:05:16,320 always remember in terms of the entropy 189 00:05:16,320 --> 00:05:18,410 always remember in terms of the entropy and since the entropy is a state 190 00:05:18,410 --> 00:05:18,420 and since the entropy is a state 191 00:05:18,420 --> 00:05:23,300 and since the entropy is a state function then the entropy change of a 192 00:05:23,300 --> 00:05:23,310 function then the entropy change of a 193 00:05:23,310 --> 00:05:27,200 function then the entropy change of a process will be given as the initial 194 00:05:27,200 --> 00:05:27,210 process will be given as the initial 195 00:05:27,210 --> 00:05:30,170 process will be given as the initial final entropy of the system minus the 196 00:05:30,170 --> 00:05:30,180 final entropy of the system minus the 197 00:05:30,180 --> 00:05:32,000 final entropy of the system minus the initial entropy of the system this is 198 00:05:32,000 --> 00:05:32,010 initial entropy of the system this is 199 00:05:32,010 --> 00:05:34,220 initial entropy of the system this is going to be Delta as again depending on 200 00:05:34,220 --> 00:05:34,230 going to be Delta as again depending on 201 00:05:34,230 --> 00:05:36,770 going to be Delta as again depending on the sign of Delta as if it is positive 202 00:05:36,770 --> 00:05:36,780 the sign of Delta as if it is positive 203 00:05:36,780 --> 00:05:38,870 the sign of Delta as if it is positive means there is an increase in the 204 00:05:38,870 --> 00:05:38,880 means there is an increase in the 205 00:05:38,880 --> 00:05:40,940 means there is an increase in the entropy and if it is negative that means 206 00:05:40,940 --> 00:05:40,950 entropy and if it is negative that means 207 00:05:40,950 --> 00:05:42,500 entropy and if it is negative that means there is a decrease in the entropy of 208 00:05:42,500 --> 00:05:42,510 there is a decrease in the entropy of 209 00:05:42,510 --> 00:05:45,380 there is a decrease in the entropy of the system this is a gain for the system 210 00:05:45,380 --> 00:05:45,390 the system this is a gain for the system 211 00:05:45,390 --> 00:05:53,320 the system this is a gain for the system yes how do we define order in chemistry 212 00:05:53,320 --> 00:05:53,330 yes how do we define order in chemistry 213 00:05:53,330 --> 00:05:57,950 yes how do we define order in chemistry okay if you have let's say a pure 214 00:05:57,950 --> 00:05:57,960 okay if you have let's say a pure 215 00:05:57,960 --> 00:06:02,380 okay if you have let's say a pure crystalline substance pure crystalline 216 00:06:02,380 --> 00:06:02,390 crystalline substance pure crystalline 217 00:06:02,390 --> 00:06:11,920 crystalline substance pure crystalline at zero Kelvin it is the maximum order 218 00:06:11,920 --> 00:06:11,930 at zero Kelvin it is the maximum order 219 00:06:11,930 --> 00:06:15,170 at zero Kelvin it is the maximum order right now if you increase the 220 00:06:15,170 --> 00:06:15,180 right now if you increase the 221 00:06:15,180 --> 00:06:16,970 right now if you increase the temperature from there that take that 222 00:06:16,970 --> 00:06:16,980 temperature from there that take that 223 00:06:16,980 --> 00:06:19,070 temperature from there that take that crystal increase now zero Kelvin 224 00:06:19,070 --> 00:06:19,080 crystal increase now zero Kelvin 225 00:06:19,080 --> 00:06:22,300 crystal increase now zero Kelvin remember zero Kelvin that means every 226 00:06:22,300 --> 00:06:22,310 remember zero Kelvin that means every 227 00:06:22,310 --> 00:06:24,980 remember zero Kelvin that means every vibrational rotational translational 228 00:06:24,980 --> 00:06:24,990 vibrational rotational translational 229 00:06:24,990 --> 00:06:31,600 vibrational rotational translational motions stopped so we have an actually a 230 00:06:31,600 --> 00:06:31,610 motions stopped so we have an actually a 231 00:06:31,610 --> 00:06:35,300 motions stopped so we have an actually a maximum order of the atoms or the 232 00:06:35,300 --> 00:06:35,310 maximum order of the atoms or the 233 00:06:35,310 --> 00:06:37,490 maximum order of the atoms or the molecules or the ions in the crystal 234 00:06:37,490 --> 00:06:37,500 molecules or the ions in the crystal 235 00:06:37,500 --> 00:06:42,080 molecules or the ions in the crystal that is the 100% water now when you have 236 00:06:42,080 --> 00:06:42,090 that is the 100% water now when you have 237 00:06:42,090 --> 00:06:44,210 that is the 100% water now when you have 100% order as we will talk about that 238 00:06:44,210 --> 00:06:44,220 100% order as we will talk about that 239 00:06:44,220 --> 00:06:47,210 100% order as we will talk about that again few minutes later that means that 240 00:06:47,210 --> 00:06:47,220 again few minutes later that means that 241 00:06:47,220 --> 00:06:51,350 again few minutes later that means that the entropy is what yes the entropy is 242 00:06:51,350 --> 00:06:51,360 the entropy is what yes the entropy is 243 00:06:51,360 --> 00:06:56,360 the entropy is what yes the entropy is zero right if you have real order simply 244 00:06:56,360 --> 00:06:56,370 zero right if you have real order simply 245 00:06:56,370 --> 00:06:58,279 zero right if you have real order simply entropy zero 246 00:06:58,279 --> 00:06:58,289 entropy zero 247 00:06:58,289 --> 00:07:00,049 entropy zero then if you increase the temperature 248 00:07:00,049 --> 00:07:00,059 then if you increase the temperature 249 00:07:00,059 --> 00:07:02,389 then if you increase the temperature then the molecule will start moving 250 00:07:02,389 --> 00:07:02,399 then the molecule will start moving 251 00:07:02,399 --> 00:07:04,070 then the molecule will start moving around making vibrational rotational 252 00:07:04,070 --> 00:07:04,080 around making vibrational rotational 253 00:07:04,080 --> 00:07:07,519 around making vibrational rotational motions and they can probably melt from 254 00:07:07,519 --> 00:07:07,529 motions and they can probably melt from 255 00:07:07,529 --> 00:07:10,969 motions and they can probably melt from solid to the liquid again freedom of 256 00:07:10,969 --> 00:07:10,979 solid to the liquid again freedom of 257 00:07:10,979 --> 00:07:13,189 solid to the liquid again freedom of movement increases and so on that means 258 00:07:13,189 --> 00:07:13,199 movement increases and so on that means 259 00:07:13,199 --> 00:07:17,980 movement increases and so on that means the entropy increases okay so we that's 260 00:07:17,980 --> 00:07:17,990 the entropy increases okay so we that's 261 00:07:17,990 --> 00:07:21,549 the entropy increases okay so we that's actually we have to think about the 262 00:07:21,549 --> 00:07:21,559 actually we have to think about the 263 00:07:21,559 --> 00:07:24,739 actually we have to think about the motions of the molecules when we think 264 00:07:24,739 --> 00:07:24,749 motions of the molecules when we think 265 00:07:24,749 --> 00:07:27,559 motions of the molecules when we think about the order in chemistry right 266 00:07:27,559 --> 00:07:27,569 about the order in chemistry right 267 00:07:27,569 --> 00:07:29,749 about the order in chemistry right motions of tomorrow we will talk about 268 00:07:29,749 --> 00:07:29,759 motions of tomorrow we will talk about 269 00:07:29,759 --> 00:07:31,489 motions of tomorrow we will talk about that more actually yes 270 00:07:31,489 --> 00:07:31,499 that more actually yes 271 00:07:31,499 --> 00:07:37,429 that more actually yes so now again we can simply calculate the 272 00:07:37,429 --> 00:07:37,439 so now again we can simply calculate the 273 00:07:37,439 --> 00:07:42,469 so now again we can simply calculate the entropy of change if you know the Q 274 00:07:42,469 --> 00:07:42,479 entropy of change if you know the Q 275 00:07:42,479 --> 00:07:45,409 entropy of change if you know the Q reversible for that process that means 276 00:07:45,409 --> 00:07:45,419 reversible for that process that means 277 00:07:45,419 --> 00:07:47,359 reversible for that process that means if you have the heat involved in a 278 00:07:47,359 --> 00:07:47,369 if you have the heat involved in a 279 00:07:47,369 --> 00:07:50,779 if you have the heat involved in a reversible process we can calculate the 280 00:07:50,779 --> 00:07:50,789 reversible process we can calculate the 281 00:07:50,789 --> 00:07:52,519 reversible process we can calculate the entropy change for that process must 282 00:07:52,519 --> 00:07:52,529 entropy change for that process must 283 00:07:52,529 --> 00:07:56,420 entropy change for that process must just divide in the heat involved that is 284 00:07:56,420 --> 00:07:56,430 just divide in the heat involved that is 285 00:07:56,430 --> 00:07:58,820 just divide in the heat involved that is the reversible process divided by the 286 00:07:58,820 --> 00:07:58,830 the reversible process divided by the 287 00:07:58,830 --> 00:08:00,320 the reversible process divided by the temperature and this temperature has to 288 00:08:00,320 --> 00:08:00,330 temperature and this temperature has to 289 00:08:00,330 --> 00:08:03,019 temperature and this temperature has to be constant again right that has to be 290 00:08:03,019 --> 00:08:03,029 be constant again right that has to be 291 00:08:03,029 --> 00:08:07,209 be constant again right that has to be constant okay now second law of 292 00:08:07,209 --> 00:08:07,219 constant okay now second law of 293 00:08:07,219 --> 00:08:09,439 constant okay now second law of thermodynamics remember first law is 294 00:08:09,439 --> 00:08:09,449 thermodynamics remember first law is 295 00:08:09,449 --> 00:08:13,369 thermodynamics remember first law is about the energy of the universe which 296 00:08:13,369 --> 00:08:13,379 about the energy of the universe which 297 00:08:13,379 --> 00:08:14,989 about the energy of the universe which says it's constant there were changes 298 00:08:14,989 --> 00:08:14,999 says it's constant there were changes 299 00:08:14,999 --> 00:08:17,420 says it's constant there were changes this is the second law now the second 300 00:08:17,420 --> 00:08:17,430 this is the second law now the second 301 00:08:17,430 --> 00:08:19,579 this is the second law now the second law of the universe again as we talk the 302 00:08:19,579 --> 00:08:19,589 law of the universe again as we talk the 303 00:08:19,589 --> 00:08:21,559 law of the universe again as we talk the entropy of the universe in a spontaneous 304 00:08:21,559 --> 00:08:21,569 entropy of the universe in a spontaneous 305 00:08:21,569 --> 00:08:24,579 entropy of the universe in a spontaneous process in any spontaneous process 306 00:08:24,579 --> 00:08:24,589 process in any spontaneous process 307 00:08:24,589 --> 00:08:27,589 process in any spontaneous process increases as we said last time the 308 00:08:27,589 --> 00:08:27,599 increases as we said last time the 309 00:08:27,599 --> 00:08:30,499 increases as we said last time the entropy and the internal energy behaves 310 00:08:30,499 --> 00:08:30,509 entropy and the internal energy behaves 311 00:08:30,509 --> 00:08:33,189 entropy and the internal energy behaves differently in this case like the total 312 00:08:33,189 --> 00:08:33,199 differently in this case like the total 313 00:08:33,199 --> 00:08:35,149 differently in this case like the total internal energy total energy of the 314 00:08:35,149 --> 00:08:35,159 internal energy total energy of the 315 00:08:35,159 --> 00:08:37,790 internal energy total energy of the universe is constant right as we said in 316 00:08:37,790 --> 00:08:37,800 universe is constant right as we said in 317 00:08:37,800 --> 00:08:41,149 universe is constant right as we said in the first law of thermodynamics but the 318 00:08:41,149 --> 00:08:41,159 the first law of thermodynamics but the 319 00:08:41,159 --> 00:08:44,960 the first law of thermodynamics but the entropy of the universe is not constant 320 00:08:44,960 --> 00:08:44,970 entropy of the universe is not constant 321 00:08:44,970 --> 00:08:49,670 entropy of the universe is not constant it always increases with spontaneous 322 00:08:49,670 --> 00:08:49,680 it always increases with spontaneous 323 00:08:49,680 --> 00:08:51,829 it always increases with spontaneous processes when spontaneous processes are 324 00:08:51,829 --> 00:08:51,839 processes when spontaneous processes are 325 00:08:51,839 --> 00:08:53,900 processes when spontaneous processes are taking place the entropy increases this 326 00:08:53,900 --> 00:08:53,910 taking place the entropy increases this 327 00:08:53,910 --> 00:08:57,350 taking place the entropy increases this is the second law of thermodynamics what 328 00:08:57,350 --> 00:08:57,360 is the second law of thermodynamics what 329 00:08:57,360 --> 00:08:58,999 is the second law of thermodynamics what it means again in equations that they 330 00:08:58,999 --> 00:08:59,009 it means again in equations that they 331 00:08:59,009 --> 00:09:01,370 it means again in equations that they put it in the equation form Delta s 332 00:09:01,370 --> 00:09:01,380 put it in the equation form Delta s 333 00:09:01,380 --> 00:09:04,490 put it in the equation form Delta s universe will simply be greater than 334 00:09:04,490 --> 00:09:04,500 universe will simply be greater than 335 00:09:04,500 --> 00:09:08,660 universe will simply be greater than zero for spa for irreversible process 336 00:09:08,660 --> 00:09:08,670 zero for spa for irreversible process 337 00:09:08,670 --> 00:09:12,230 zero for spa for irreversible process remember all irreversible processes are 338 00:09:12,230 --> 00:09:12,240 remember all irreversible processes are 339 00:09:12,240 --> 00:09:14,750 remember all irreversible processes are spontaneous processes actually so that 340 00:09:14,750 --> 00:09:14,760 spontaneous processes actually so that 341 00:09:14,760 --> 00:09:17,210 spontaneous processes actually so that spontaneous process the entropy of the 342 00:09:17,210 --> 00:09:17,220 spontaneous process the entropy of the 343 00:09:17,220 --> 00:09:20,269 spontaneous process the entropy of the universe increases now what happens it 344 00:09:20,269 --> 00:09:20,279 universe increases now what happens it 345 00:09:20,279 --> 00:09:23,480 universe increases now what happens it says if the process is reversible what 346 00:09:23,480 --> 00:09:23,490 says if the process is reversible what 347 00:09:23,490 --> 00:09:25,550 says if the process is reversible what does that mean that means equilibrium in 348 00:09:25,550 --> 00:09:25,560 does that mean that means equilibrium in 349 00:09:25,560 --> 00:09:28,670 does that mean that means equilibrium in that case the entropy of the universe is 350 00:09:28,670 --> 00:09:28,680 that case the entropy of the universe is 351 00:09:28,680 --> 00:09:30,860 that case the entropy of the universe is not increasing it's equal to constant 352 00:09:30,860 --> 00:09:30,870 not increasing it's equal to constant 353 00:09:30,870 --> 00:09:33,560 not increasing it's equal to constant value again now so remember again now 354 00:09:33,560 --> 00:09:33,570 value again now so remember again now 355 00:09:33,570 --> 00:09:36,230 value again now so remember again now dropping this here it's a spontaneous 356 00:09:36,230 --> 00:09:36,240 dropping this here it's a spontaneous 357 00:09:36,240 --> 00:09:38,690 dropping this here it's a spontaneous process that means that the entropy of 358 00:09:38,690 --> 00:09:38,700 process that means that the entropy of 359 00:09:38,700 --> 00:09:41,540 process that means that the entropy of the universe increased certain amount 360 00:09:41,540 --> 00:09:41,550 the universe increased certain amount 361 00:09:41,550 --> 00:09:44,480 the universe increased certain amount right now if I take this from here and 362 00:09:44,480 --> 00:09:44,490 right now if I take this from here and 363 00:09:44,490 --> 00:09:47,000 right now if I take this from here and bring it up here what happens in the 364 00:09:47,000 --> 00:09:47,010 bring it up here what happens in the 365 00:09:47,010 --> 00:09:53,930 bring it up here what happens in the entropy of the universe increase or 366 00:09:53,930 --> 00:09:53,940 entropy of the universe increase or 367 00:09:53,940 --> 00:10:00,760 entropy of the universe increase or decrease hmm is this process spontaneous 368 00:10:00,760 --> 00:10:00,770 decrease hmm is this process spontaneous 369 00:10:00,770 --> 00:10:07,460 decrease hmm is this process spontaneous no right so when it's not actually this 370 00:10:07,460 --> 00:10:07,470 no right so when it's not actually this 371 00:10:07,470 --> 00:10:08,930 no right so when it's not actually this is not spontaneous but it's is it 372 00:10:08,930 --> 00:10:08,940 is not spontaneous but it's is it 373 00:10:08,940 --> 00:10:10,610 is not spontaneous but it's is it reversible let's put it that way 374 00:10:10,610 --> 00:10:10,620 reversible let's put it that way 375 00:10:10,620 --> 00:10:12,710 reversible let's put it that way is it reversible it's not spontaneous 376 00:10:12,710 --> 00:10:12,720 is it reversible it's not spontaneous 377 00:10:12,720 --> 00:10:16,070 is it reversible it's not spontaneous but is it reversible no it is not 378 00:10:16,070 --> 00:10:16,080 but is it reversible no it is not 379 00:10:16,080 --> 00:10:16,760 but is it reversible no it is not reversible 380 00:10:16,760 --> 00:10:16,770 reversible 381 00:10:16,770 --> 00:10:18,800 reversible therefore again the entropy of the 382 00:10:18,800 --> 00:10:18,810 therefore again the entropy of the 383 00:10:18,810 --> 00:10:21,230 therefore again the entropy of the universe is increased now to have a 384 00:10:21,230 --> 00:10:21,240 universe is increased now to have a 385 00:10:21,240 --> 00:10:26,840 universe is increased now to have a reversible process dropping or taking it 386 00:10:26,840 --> 00:10:26,850 reversible process dropping or taking it 387 00:10:26,850 --> 00:10:29,300 reversible process dropping or taking it out to make it reversible what should I 388 00:10:29,300 --> 00:10:29,310 out to make it reversible what should I 389 00:10:29,310 --> 00:10:35,120 out to make it reversible what should I do it should probably take almost like 390 00:10:35,120 --> 00:10:35,130 do it should probably take almost like 391 00:10:35,130 --> 00:10:37,880 do it should probably take almost like years and years to bring it from up here 392 00:10:37,880 --> 00:10:37,890 years and years to bring it from up here 393 00:10:37,890 --> 00:10:41,480 years and years to bring it from up here to down there such that you know keep it 394 00:10:41,480 --> 00:10:41,490 to down there such that you know keep it 395 00:10:41,490 --> 00:10:44,000 to down there such that you know keep it at equilibrium sort of like always in 396 00:10:44,000 --> 00:10:44,010 at equilibrium sort of like always in 397 00:10:44,010 --> 00:10:45,800 at equilibrium sort of like always in equilibrium phase which is you know 398 00:10:45,800 --> 00:10:45,810 equilibrium phase which is you know 399 00:10:45,810 --> 00:10:48,220 equilibrium phase which is you know that's again not possible to do that but 400 00:10:48,220 --> 00:10:48,230 that's again not possible to do that but 401 00:10:48,230 --> 00:10:52,150 that's again not possible to do that but again both dropping taking it out are 402 00:10:52,150 --> 00:10:52,160 again both dropping taking it out are 403 00:10:52,160 --> 00:10:54,769 again both dropping taking it out are irreversible processes and all 404 00:10:54,769 --> 00:10:54,779 irreversible processes and all 405 00:10:54,779 --> 00:10:56,810 irreversible processes and all irreversible processes the entropy of 406 00:10:56,810 --> 00:10:56,820 irreversible processes the entropy of 407 00:10:56,820 --> 00:10:59,780 irreversible processes the entropy of the universe increases irreversible 408 00:10:59,780 --> 00:10:59,790 the universe increases irreversible 409 00:10:59,790 --> 00:11:01,010 the universe increases irreversible process and if the entropy of the 410 00:11:01,010 --> 00:11:01,020 process and if the entropy of the 411 00:11:01,020 --> 00:11:07,460 process and if the entropy of the universe increases okay now entropy in 412 00:11:07,460 --> 00:11:07,470 universe increases okay now entropy in 413 00:11:07,470 --> 00:11:11,210 universe increases okay now entropy in the molecular scale again like we talked 414 00:11:11,210 --> 00:11:11,220 the molecular scale again like we talked 415 00:11:11,220 --> 00:11:14,800 the molecular scale again like we talked about last time when you have two 416 00:11:14,800 --> 00:11:14,810 about last time when you have two 417 00:11:14,810 --> 00:11:18,319 about last time when you have two molecules containing this flask over 418 00:11:18,319 --> 00:11:18,329 molecules containing this flask over 419 00:11:18,329 --> 00:11:21,050 molecules containing this flask over here and this flask is empty when we 420 00:11:21,050 --> 00:11:21,060 here and this flask is empty when we 421 00:11:21,060 --> 00:11:23,170 here and this flask is empty when we open it up that means that this 422 00:11:23,170 --> 00:11:23,180 open it up that means that this 423 00:11:23,180 --> 00:11:25,190 open it up that means that this molecules will move 424 00:11:25,190 --> 00:11:25,200 molecules will move 425 00:11:25,200 --> 00:11:27,230 molecules will move to here actually if you have more 426 00:11:27,230 --> 00:11:27,240 to here actually if you have more 427 00:11:27,240 --> 00:11:29,180 to here actually if you have more molecules and I will move all over fill 428 00:11:29,180 --> 00:11:29,190 molecules and I will move all over fill 429 00:11:29,190 --> 00:11:31,180 molecules and I will move all over fill out the whole things and this is a 430 00:11:31,180 --> 00:11:31,190 out the whole things and this is a 431 00:11:31,190 --> 00:11:34,280 out the whole things and this is a spontaneous process a spontaneous 432 00:11:34,280 --> 00:11:34,290 spontaneous process a spontaneous 433 00:11:34,290 --> 00:11:36,770 spontaneous process a spontaneous process what does that means that means 434 00:11:36,770 --> 00:11:36,780 process what does that means that means 435 00:11:36,780 --> 00:11:39,560 process what does that means that means that the entropy of the universe should 436 00:11:39,560 --> 00:11:39,570 that the entropy of the universe should 437 00:11:39,570 --> 00:11:44,000 that the entropy of the universe should increase right and it does actually 438 00:11:44,000 --> 00:11:44,010 increase right and it does actually 439 00:11:44,010 --> 00:11:47,570 increase right and it does actually because when you simply open this valve 440 00:11:47,570 --> 00:11:47,580 because when you simply open this valve 441 00:11:47,580 --> 00:11:51,260 because when you simply open this valve here and let this molecules simply 442 00:11:51,260 --> 00:11:51,270 here and let this molecules simply 443 00:11:51,270 --> 00:11:53,570 here and let this molecules simply diffuse or a fuse into this if this is 444 00:11:53,570 --> 00:11:53,580 diffuse or a fuse into this if this is 445 00:11:53,580 --> 00:11:57,020 diffuse or a fuse into this if this is vacuum effusion over here then there 446 00:11:57,020 --> 00:11:57,030 vacuum effusion over here then there 447 00:11:57,030 --> 00:12:00,380 vacuum effusion over here then there will be four possible distributions of 448 00:12:00,380 --> 00:12:00,390 will be four possible distributions of 449 00:12:00,390 --> 00:12:03,560 will be four possible distributions of these two molecules in two flasks 450 00:12:03,560 --> 00:12:03,570 these two molecules in two flasks 451 00:12:03,570 --> 00:12:07,730 these two molecules in two flasks right now the simply if you consider for 452 00:12:07,730 --> 00:12:07,740 right now the simply if you consider for 453 00:12:07,740 --> 00:12:11,990 right now the simply if you consider for example any of the gas molecules blue or 454 00:12:11,990 --> 00:12:12,000 example any of the gas molecules blue or 455 00:12:12,000 --> 00:12:14,900 example any of the gas molecules blue or red being in this flask in this class 456 00:12:14,900 --> 00:12:14,910 red being in this flask in this class 457 00:12:14,910 --> 00:12:18,590 red being in this flask in this class the probability will be 2 over 4 that 458 00:12:18,590 --> 00:12:18,600 the probability will be 2 over 4 that 459 00:12:18,600 --> 00:12:22,520 the probability will be 2 over 4 that means 1 over 2 or if you simply consider 460 00:12:22,520 --> 00:12:22,530 means 1 over 2 or if you simply consider 461 00:12:22,530 --> 00:12:25,790 means 1 over 2 or if you simply consider two molecules being here again the 462 00:12:25,790 --> 00:12:25,800 two molecules being here again the 463 00:12:25,800 --> 00:12:29,810 two molecules being here again the probability is 1 over 4 right 1 over 4 464 00:12:29,810 --> 00:12:29,820 probability is 1 over 4 right 1 over 4 465 00:12:29,820 --> 00:12:34,990 probability is 1 over 4 right 1 over 4 and so on so in other words the 466 00:12:34,990 --> 00:12:35,000 and so on so in other words the 467 00:12:35,000 --> 00:12:39,620 and so on so in other words the probability of having two molecules in 468 00:12:39,620 --> 00:12:39,630 probability of having two molecules in 469 00:12:39,630 --> 00:12:41,810 probability of having two molecules in the same flask is much less than 470 00:12:41,810 --> 00:12:41,820 the same flask is much less than 471 00:12:41,820 --> 00:12:44,690 the same flask is much less than probability of having one molecule in 472 00:12:44,690 --> 00:12:44,700 probability of having one molecule in 473 00:12:44,700 --> 00:12:46,400 probability of having one molecule in one class and the other one and the 474 00:12:46,400 --> 00:12:46,410 one class and the other one and the 475 00:12:46,410 --> 00:12:50,210 one class and the other one and the others now consider you dealing with one 476 00:12:50,210 --> 00:12:50,220 others now consider you dealing with one 477 00:12:50,220 --> 00:12:54,290 others now consider you dealing with one mole of gases how many molecules of gas 478 00:12:54,290 --> 00:12:54,300 mole of gases how many molecules of gas 479 00:12:54,300 --> 00:12:56,750 mole of gases how many molecules of gas we have am pagano's number of molecules 480 00:12:56,750 --> 00:12:56,760 we have am pagano's number of molecules 481 00:12:56,760 --> 00:12:58,580 we have am pagano's number of molecules and remember the Avogadro's number is 482 00:12:58,580 --> 00:12:58,590 and remember the Avogadro's number is 483 00:12:58,590 --> 00:13:02,780 and remember the Avogadro's number is very very large number 602 times 10 to 484 00:13:02,780 --> 00:13:02,790 very very large number 602 times 10 to 485 00:13:02,790 --> 00:13:05,870 very very large number 602 times 10 to the minus 10 to the 23 that's a big 486 00:13:05,870 --> 00:13:05,880 the minus 10 to the 23 that's a big 487 00:13:05,880 --> 00:13:07,400 the minus 10 to the 23 that's a big number it's actually bigger than we can 488 00:13:07,400 --> 00:13:07,410 number it's actually bigger than we can 489 00:13:07,410 --> 00:13:08,030 number it's actually bigger than we can imagine 490 00:13:08,030 --> 00:13:08,040 imagine 491 00:13:08,040 --> 00:13:13,160 imagine we can simply and in that case if you 492 00:13:13,160 --> 00:13:13,170 we can simply and in that case if you 493 00:13:13,170 --> 00:13:16,520 we can simply and in that case if you have one mole then the probability of 494 00:13:16,520 --> 00:13:16,530 have one mole then the probability of 495 00:13:16,530 --> 00:13:22,210 have one mole then the probability of having one distribution or having all 496 00:13:22,210 --> 00:13:22,220 497 00:13:22,220 --> 00:13:26,210 gas molecules being in the same flask 498 00:13:26,210 --> 00:13:26,220 gas molecules being in the same flask 499 00:13:26,220 --> 00:13:30,590 gas molecules being in the same flask will be 1 over 2 power to the Avogadro's 500 00:13:30,590 --> 00:13:30,600 will be 1 over 2 power to the Avogadro's 501 00:13:30,600 --> 00:13:34,760 will be 1 over 2 power to the Avogadro's number that is 1 over 2 power 2 to the 502 00:13:34,760 --> 00:13:34,770 number that is 1 over 2 power 2 to the 503 00:13:34,770 --> 00:13:37,820 number that is 1 over 2 power 2 to the 10 to the 23 something like that what 504 00:13:37,820 --> 00:13:37,830 10 to the 23 something like that what 505 00:13:37,830 --> 00:13:38,620 10 to the 23 something like that what does that means 506 00:13:38,620 --> 00:13:38,630 does that means 507 00:13:38,630 --> 00:13:42,360 does that means there will be very very large number of 508 00:13:42,360 --> 00:13:42,370 there will be very very large number of 509 00:13:42,370 --> 00:13:45,370 there will be very very large number of different ways of distributing actually 510 00:13:45,370 --> 00:13:45,380 different ways of distributing actually 511 00:13:45,380 --> 00:13:48,610 different ways of distributing actually one mole of gas into two flats and the 512 00:13:48,610 --> 00:13:48,620 one mole of gas into two flats and the 513 00:13:48,620 --> 00:13:52,920 one mole of gas into two flats and the probability of having all gases in one 514 00:13:52,920 --> 00:13:52,930 probability of having all gases in one 515 00:13:52,930 --> 00:13:59,380 probability of having all gases in one flask will be very close to zero it will 516 00:13:59,380 --> 00:13:59,390 flask will be very close to zero it will 517 00:13:59,390 --> 00:14:03,220 flask will be very close to zero it will be like 1 over infinite almost right so 518 00:14:03,220 --> 00:14:03,230 be like 1 over infinite almost right so 519 00:14:03,230 --> 00:14:06,640 be like 1 over infinite almost right so that means that the molecules when you 520 00:14:06,640 --> 00:14:06,650 that means that the molecules when you 521 00:14:06,650 --> 00:14:14,260 that means that the molecules when you let this flat simply open this switch 522 00:14:14,260 --> 00:14:14,270 let this flat simply open this switch 523 00:14:14,270 --> 00:14:16,990 let this flat simply open this switch here and let them go here they will 524 00:14:16,990 --> 00:14:17,000 here and let them go here they will 525 00:14:17,000 --> 00:14:20,170 here and let them go here they will never be back again both here as a 526 00:14:20,170 --> 00:14:20,180 never be back again both here as a 527 00:14:20,180 --> 00:14:21,730 never be back again both here as a matter of fact especially if you're 528 00:14:21,730 --> 00:14:21,740 matter of fact especially if you're 529 00:14:21,740 --> 00:14:24,670 matter of fact especially if you're dealing with large number of molecules 530 00:14:24,670 --> 00:14:24,680 dealing with large number of molecules 531 00:14:24,680 --> 00:14:29,880 dealing with large number of molecules large number of molecules and again the 532 00:14:29,880 --> 00:14:29,890 large number of molecules and again the 533 00:14:29,890 --> 00:14:35,110 large number of molecules and again the entropy of the system will be related to 534 00:14:35,110 --> 00:14:35,120 entropy of the system will be related to 535 00:14:35,120 --> 00:14:38,680 entropy of the system will be related to the number of different distributions of 536 00:14:38,680 --> 00:14:38,690 the number of different distributions of 537 00:14:38,690 --> 00:14:42,240 the number of different distributions of these molecules into this glass air 2 538 00:14:42,240 --> 00:14:42,250 these molecules into this glass air 2 539 00:14:42,250 --> 00:14:46,270 these molecules into this glass air 2 flask again and simply in this case like 540 00:14:46,270 --> 00:14:46,280 flask again and simply in this case like 541 00:14:46,280 --> 00:14:47,950 flask again and simply in this case like when you have this over here there's 542 00:14:47,950 --> 00:14:47,960 when you have this over here there's 543 00:14:47,960 --> 00:14:49,780 when you have this over here there's only one way to submit in that there's 544 00:14:49,780 --> 00:14:49,790 only one way to submit in that there's 545 00:14:49,790 --> 00:14:51,370 only one way to submit in that there's two of those in the same flat 546 00:14:51,370 --> 00:14:51,380 two of those in the same flat 547 00:14:51,380 --> 00:14:55,360 two of those in the same flat but when you open the valve here and let 548 00:14:55,360 --> 00:14:55,370 but when you open the valve here and let 549 00:14:55,370 --> 00:14:58,090 but when you open the valve here and let the two these two molecules expand and 550 00:14:58,090 --> 00:14:58,100 the two these two molecules expand and 551 00:14:58,100 --> 00:15:00,370 the two these two molecules expand and there will be four distributions 552 00:15:00,370 --> 00:15:00,380 there will be four distributions 553 00:15:00,380 --> 00:15:02,320 there will be four distributions and if you have more there will be more 554 00:15:02,320 --> 00:15:02,330 and if you have more there will be more 555 00:15:02,330 --> 00:15:04,120 and if you have more there will be more distributions and more distributions and 556 00:15:04,120 --> 00:15:04,130 distributions and more distributions and 557 00:15:04,130 --> 00:15:05,320 distributions and more distributions and more distributions depending on the 558 00:15:05,320 --> 00:15:05,330 more distributions depending on the 559 00:15:05,330 --> 00:15:07,150 more distributions depending on the number of molecules that means more 560 00:15:07,150 --> 00:15:07,160 number of molecules that means more 561 00:15:07,160 --> 00:15:10,450 number of molecules that means more distributions means that the entropy of 562 00:15:10,450 --> 00:15:10,460 distributions means that the entropy of 563 00:15:10,460 --> 00:15:13,150 distributions means that the entropy of the system is increasing the entropy of 564 00:15:13,150 --> 00:15:13,160 the system is increasing the entropy of 565 00:15:13,160 --> 00:15:16,630 the system is increasing the entropy of the system is increasing because having 566 00:15:16,630 --> 00:15:16,640 the system is increasing because having 567 00:15:16,640 --> 00:15:21,280 the system is increasing because having one distribution in fact probability of 568 00:15:21,280 --> 00:15:21,290 one distribution in fact probability of 569 00:15:21,290 --> 00:15:23,350 one distribution in fact probability of heaven one distribution would be 1 over 570 00:15:23,350 --> 00:15:23,360 heaven one distribution would be 1 over 571 00:15:23,360 --> 00:15:26,520 heaven one distribution would be 1 over that very large number and that number 572 00:15:26,520 --> 00:15:26,530 that very large number and that number 573 00:15:26,530 --> 00:15:29,710 that very large number and that number goes to infinity and the probability of 574 00:15:29,710 --> 00:15:29,720 goes to infinity and the probability of 575 00:15:29,720 --> 00:15:32,470 goes to infinity and the probability of heaven that particular arrangement will 576 00:15:32,470 --> 00:15:32,480 heaven that particular arrangement will 577 00:15:32,480 --> 00:15:34,750 heaven that particular arrangement will be close to zero actually right close to 578 00:15:34,750 --> 00:15:34,760 be close to zero actually right close to 579 00:15:34,760 --> 00:15:41,620 be close to zero actually right close to zero now the question here is how can we 580 00:15:41,620 --> 00:15:41,630 zero now the question here is how can we 581 00:15:41,630 --> 00:15:49,030 zero now the question here is how can we relate the entropy to the molecules at 582 00:15:49,030 --> 00:15:49,040 relate the entropy to the molecules at 583 00:15:49,040 --> 00:15:52,120 relate the entropy to the molecules at the molecular level molecular motions 584 00:15:52,120 --> 00:15:52,130 the molecular level molecular motions 585 00:15:52,130 --> 00:15:55,320 the molecular level molecular motions the system now remember again the 586 00:15:55,320 --> 00:15:55,330 the system now remember again the 587 00:15:55,330 --> 00:15:57,430 the system now remember again the thermodynamics particularly looks at the 588 00:15:57,430 --> 00:15:57,440 thermodynamics particularly looks at the 589 00:15:57,440 --> 00:15:59,320 thermodynamics particularly looks at the ball properties it said like we have a 590 00:15:59,320 --> 00:15:59,330 ball properties it said like we have a 591 00:15:59,330 --> 00:16:01,690 ball properties it said like we have a substances it's a big picture you know 592 00:16:01,690 --> 00:16:01,700 substances it's a big picture you know 593 00:16:01,700 --> 00:16:04,870 substances it's a big picture you know we for example you just take this here 594 00:16:04,870 --> 00:16:04,880 we for example you just take this here 595 00:16:04,880 --> 00:16:06,880 we for example you just take this here this pointer and if you take consider 596 00:16:06,880 --> 00:16:06,890 this pointer and if you take consider 597 00:16:06,890 --> 00:16:09,340 this pointer and if you take consider this whole things that's the bulk things 598 00:16:09,340 --> 00:16:09,350 this whole things that's the bulk things 599 00:16:09,350 --> 00:16:10,990 this whole things that's the bulk things right and it's hard it's a both 600 00:16:10,990 --> 00:16:11,000 right and it's hard it's a both 601 00:16:11,000 --> 00:16:12,250 right and it's hard it's a both properties and other things the 602 00:16:12,250 --> 00:16:12,260 properties and other things the 603 00:16:12,260 --> 00:16:14,860 properties and other things the temperature and so on but if you go to 604 00:16:14,860 --> 00:16:14,870 temperature and so on but if you go to 605 00:16:14,870 --> 00:16:19,090 temperature and so on but if you go to the molecular level an atomic level that 606 00:16:19,090 --> 00:16:19,100 the molecular level an atomic level that 607 00:16:19,100 --> 00:16:21,040 the molecular level an atomic level that means we start thinking about what is 608 00:16:21,040 --> 00:16:21,050 means we start thinking about what is 609 00:16:21,050 --> 00:16:22,480 means we start thinking about what is this made of 610 00:16:22,480 --> 00:16:22,490 this made of 611 00:16:22,490 --> 00:16:26,380 this made of what atoms carbon hydrogen oxygen maybe 612 00:16:26,380 --> 00:16:26,390 what atoms carbon hydrogen oxygen maybe 613 00:16:26,390 --> 00:16:28,450 what atoms carbon hydrogen oxygen maybe some other elements and so on that is 614 00:16:28,450 --> 00:16:28,460 some other elements and so on that is 615 00:16:28,460 --> 00:16:30,820 some other elements and so on that is the again the molecular atomic level 616 00:16:30,820 --> 00:16:30,830 the again the molecular atomic level 617 00:16:30,830 --> 00:16:32,860 the again the molecular atomic level what is this structure is this a 618 00:16:32,860 --> 00:16:32,870 what is this structure is this a 619 00:16:32,870 --> 00:16:34,780 what is this structure is this a crystalline type structure or a 620 00:16:34,780 --> 00:16:34,790 crystalline type structure or a 621 00:16:34,790 --> 00:16:36,880 crystalline type structure or a different type structure what is the fit 622 00:16:36,880 --> 00:16:36,890 different type structure what is the fit 623 00:16:36,890 --> 00:16:38,380 different type structure what is the fit is crystalline what is the unit cells 624 00:16:38,380 --> 00:16:38,390 is crystalline what is the unit cells 625 00:16:38,390 --> 00:16:40,990 is crystalline what is the unit cells and so on so all of these are molecular 626 00:16:40,990 --> 00:16:41,000 and so on so all of these are molecular 627 00:16:41,000 --> 00:16:42,760 and so on so all of these are molecular level properties molecular level 628 00:16:42,760 --> 00:16:42,770 level properties molecular level 629 00:16:42,770 --> 00:16:45,340 level properties molecular level properties so can we relate the entropy 630 00:16:45,340 --> 00:16:45,350 properties so can we relate the entropy 631 00:16:45,350 --> 00:16:48,330 properties so can we relate the entropy to the molecular level properties of the 632 00:16:48,330 --> 00:16:48,340 to the molecular level properties of the 633 00:16:48,340 --> 00:16:55,510 to the molecular level properties of the substances actually now how do they 634 00:16:55,510 --> 00:16:55,520 substances actually now how do they 635 00:16:55,520 --> 00:16:58,900 substances actually now how do they relate that means how the molecular 636 00:16:58,900 --> 00:16:58,910 relate that means how the molecular 637 00:16:58,910 --> 00:17:01,450 relate that means how the molecular scale molecular properties molecular 638 00:17:01,450 --> 00:17:01,460 scale molecular properties molecular 639 00:17:01,460 --> 00:17:06,160 scale molecular properties molecular motions relate to the entropy now for 640 00:17:06,160 --> 00:17:06,170 motions relate to the entropy now for 641 00:17:06,170 --> 00:17:09,689 motions relate to the entropy now for this we use it says statistical 642 00:17:09,689 --> 00:17:09,699 this we use it says statistical 643 00:17:09,699 --> 00:17:11,829 this we use it says statistical statistics and that's called the 644 00:17:11,829 --> 00:17:11,839 statistics and that's called the 645 00:17:11,839 --> 00:17:13,329 statistics and that's called the probability statistical thermodynamics 646 00:17:13,329 --> 00:17:13,339 probability statistical thermodynamics 647 00:17:13,339 --> 00:17:15,040 probability statistical thermodynamics usually this is called statistical 648 00:17:15,040 --> 00:17:15,050 usually this is called statistical 649 00:17:15,050 --> 00:17:17,290 usually this is called statistical thermodynamics and again in statistics 650 00:17:17,290 --> 00:17:17,300 thermodynamics and again in statistics 651 00:17:17,300 --> 00:17:19,890 thermodynamics and again in statistics we mostly talk about the probability 652 00:17:19,890 --> 00:17:19,900 we mostly talk about the probability 653 00:17:19,900 --> 00:17:22,990 we mostly talk about the probability right the field is called the 654 00:17:22,990 --> 00:17:23,000 right the field is called the 655 00:17:23,000 --> 00:17:26,860 right the field is called the statistical thermodynamics and then we 656 00:17:26,860 --> 00:17:26,870 statistical thermodynamics and then we 657 00:17:26,870 --> 00:17:31,330 statistical thermodynamics and then we simply talk about microstates a single 658 00:17:31,330 --> 00:17:31,340 simply talk about microstates a single 659 00:17:31,340 --> 00:17:33,460 simply talk about microstates a single possible around rate of positions and 660 00:17:33,460 --> 00:17:33,470 possible around rate of positions and 661 00:17:33,470 --> 00:17:38,610 possible around rate of positions and kinetic energy of the molecules now 662 00:17:38,610 --> 00:17:38,620 kinetic energy of the molecules now 663 00:17:38,620 --> 00:17:43,840 kinetic energy of the molecules now let's see what this is what this simply 664 00:17:43,840 --> 00:17:43,850 let's see what this is what this simply 665 00:17:43,850 --> 00:17:46,650 let's see what this is what this simply means again but let's look at what we 666 00:17:46,650 --> 00:17:46,660 means again but let's look at what we 667 00:17:46,660 --> 00:17:51,010 means again but let's look at what we actually the answer how the entropy is 668 00:17:51,010 --> 00:17:51,020 actually the answer how the entropy is 669 00:17:51,020 --> 00:17:54,580 actually the answer how the entropy is related to the atomic level properties 670 00:17:54,580 --> 00:17:54,590 related to the atomic level properties 671 00:17:54,590 --> 00:17:57,850 related to the atomic level properties atoms molecules and so on is given by 672 00:17:57,850 --> 00:17:57,860 atoms molecules and so on is given by 673 00:17:57,860 --> 00:18:04,400 atoms molecules and so on is given by Boltzmann here and 674 00:18:04,400 --> 00:18:04,410 675 00:18:04,410 --> 00:18:10,370 horsemen define the microstates many 676 00:18:10,370 --> 00:18:10,380 horsemen define the microstates many 677 00:18:10,380 --> 00:18:12,680 horsemen define the microstates many possible micro days we can look at every 678 00:18:12,680 --> 00:18:12,690 possible micro days we can look at every 679 00:18:12,690 --> 00:18:19,130 possible micro days we can look at every pic there are picture W represents the 680 00:18:19,130 --> 00:18:19,140 pic there are picture W represents the 681 00:18:19,140 --> 00:18:21,230 pic there are picture W represents the number of microstates entropy is a 682 00:18:21,230 --> 00:18:21,240 number of microstates entropy is a 683 00:18:21,240 --> 00:18:23,120 number of microstates entropy is a measure of how many micro cells are 684 00:18:23,120 --> 00:18:23,130 measure of how many micro cells are 685 00:18:23,130 --> 00:18:25,670 measure of how many micro cells are associated with a particular microscopic 686 00:18:25,670 --> 00:18:25,680 associated with a particular microscopic 687 00:18:25,680 --> 00:18:30,500 associated with a particular microscopic state with macroscopic States now the 688 00:18:30,500 --> 00:18:30,510 state with macroscopic States now the 689 00:18:30,510 --> 00:18:32,090 state with macroscopic States now the connection between the number of 690 00:18:32,090 --> 00:18:32,100 connection between the number of 691 00:18:32,100 --> 00:18:33,620 connection between the number of microstates and the entropy of the 692 00:18:33,620 --> 00:18:33,630 microstates and the entropy of the 693 00:18:33,630 --> 00:18:37,610 microstates and the entropy of the system by Boltzmann actually given as 694 00:18:37,610 --> 00:18:37,620 system by Boltzmann actually given as 695 00:18:37,620 --> 00:18:43,760 system by Boltzmann actually given as this entropy office system of whatever 696 00:18:43,760 --> 00:18:43,770 this entropy office system of whatever 697 00:18:43,770 --> 00:18:47,750 this entropy office system of whatever you're talking about would be equal to K 698 00:18:47,750 --> 00:18:47,760 you're talking about would be equal to K 699 00:18:47,760 --> 00:18:49,370 you're talking about would be equal to K which is constant it's called the 700 00:18:49,370 --> 00:18:49,380 which is constant it's called the 701 00:18:49,380 --> 00:18:51,440 which is constant it's called the Boltzmann constant the value of that is 702 00:18:51,440 --> 00:18:51,450 Boltzmann constant the value of that is 703 00:18:51,450 --> 00:18:54,200 Boltzmann constant the value of that is actually R over Avogadro's number the 704 00:18:54,200 --> 00:18:54,210 actually R over Avogadro's number the 705 00:18:54,210 --> 00:18:55,820 actually R over Avogadro's number the gas constant divided by Avogadro's 706 00:18:55,820 --> 00:18:55,830 gas constant divided by Avogadro's 707 00:18:55,830 --> 00:19:00,380 gas constant divided by Avogadro's number and natural logarithm of W now W 708 00:19:00,380 --> 00:19:00,390 number and natural logarithm of W now W 709 00:19:00,390 --> 00:19:04,610 number and natural logarithm of W now W is the number of micro State number of 710 00:19:04,610 --> 00:19:04,620 is the number of micro State number of 711 00:19:04,620 --> 00:19:05,480 is the number of micro State number of microstate 712 00:19:05,480 --> 00:19:05,490 microstate 713 00:19:05,490 --> 00:19:07,670 microstate what is a microstate I guess we have to 714 00:19:07,670 --> 00:19:07,680 what is a microstate I guess we have to 715 00:19:07,680 --> 00:19:11,930 what is a microstate I guess we have to define what a microstate is now let's 716 00:19:11,930 --> 00:19:11,940 define what a microstate is now let's 717 00:19:11,940 --> 00:19:16,250 define what a microstate is now let's assume that we simply have one mole of 718 00:19:16,250 --> 00:19:16,260 assume that we simply have one mole of 719 00:19:16,260 --> 00:19:32,750 assume that we simply have one mole of gas in a container one mole of gas at a 720 00:19:32,750 --> 00:19:32,760 gas in a container one mole of gas at a 721 00:19:32,760 --> 00:19:37,340 gas in a container one mole of gas at a pressure temperature some temperature 722 00:19:37,340 --> 00:19:37,350 pressure temperature some temperature 723 00:19:37,350 --> 00:19:44,420 pressure temperature some temperature and pressure yeah how many molecules 602 724 00:19:44,420 --> 00:19:44,430 and pressure yeah how many molecules 602 725 00:19:44,430 --> 00:19:48,170 and pressure yeah how many molecules 602 times 10 to the 23 molecules huge number 726 00:19:48,170 --> 00:19:48,180 times 10 to the 23 molecules huge number 727 00:19:48,180 --> 00:19:51,110 times 10 to the 23 molecules huge number of molecules now these molecules are 728 00:19:51,110 --> 00:19:51,120 of molecules now these molecules are 729 00:19:51,120 --> 00:19:54,620 of molecules now these molecules are simply moving in their space in all 730 00:19:54,620 --> 00:19:54,630 simply moving in their space in all 731 00:19:54,630 --> 00:19:57,170 simply moving in their space in all directions there are collisions between 732 00:19:57,170 --> 00:19:57,180 directions there are collisions between 733 00:19:57,180 --> 00:20:01,580 directions there are collisions between them and also every molecule has a 734 00:20:01,580 --> 00:20:01,590 them and also every molecule has a 735 00:20:01,590 --> 00:20:04,970 them and also every molecule has a kinetic energy right and the 736 00:20:04,970 --> 00:20:04,980 kinetic energy right and the 737 00:20:04,980 --> 00:20:06,560 kinetic energy right and the distributions of the kinetic energy 738 00:20:06,560 --> 00:20:06,570 distributions of the kinetic energy 739 00:20:06,570 --> 00:20:10,070 distributions of the kinetic energy remember with the temperature we simply 740 00:20:10,070 --> 00:20:10,080 remember with the temperature we simply 741 00:20:10,080 --> 00:20:12,590 remember with the temperature we simply have molecules with very low kinetic 742 00:20:12,590 --> 00:20:12,600 have molecules with very low kinetic 743 00:20:12,600 --> 00:20:15,200 have molecules with very low kinetic energy and then the molecules which have 744 00:20:15,200 --> 00:20:15,210 energy and then the molecules which have 745 00:20:15,210 --> 00:20:17,810 energy and then the molecules which have the average kinetic energy and then the 746 00:20:17,810 --> 00:20:17,820 the average kinetic energy and then the 747 00:20:17,820 --> 00:20:18,210 the average kinetic energy and then the Maalik 748 00:20:18,210 --> 00:20:18,220 Maalik 749 00:20:18,220 --> 00:20:19,980 Maalik which have very large kinetic energies 750 00:20:19,980 --> 00:20:19,990 which have very large kinetic energies 751 00:20:19,990 --> 00:20:23,730 which have very large kinetic energies right so they are all moving and we know 752 00:20:23,730 --> 00:20:23,740 right so they are all moving and we know 753 00:20:23,740 --> 00:20:26,750 right so they are all moving and we know that as the temperature increases the 754 00:20:26,750 --> 00:20:26,760 that as the temperature increases the 755 00:20:26,760 --> 00:20:29,600 that as the temperature increases the kinetic energy of the molecule increases 756 00:20:29,600 --> 00:20:29,610 kinetic energy of the molecule increases 757 00:20:29,610 --> 00:20:32,970 kinetic energy of the molecule increases this is how the energy is simply stored 758 00:20:32,970 --> 00:20:32,980 this is how the energy is simply stored 759 00:20:32,980 --> 00:20:35,039 this is how the energy is simply stored in the system by increase in the 760 00:20:35,039 --> 00:20:35,049 in the system by increase in the 761 00:20:35,049 --> 00:20:37,890 in the system by increase in the temperature we store there more energy 762 00:20:37,890 --> 00:20:37,900 temperature we store there more energy 763 00:20:37,900 --> 00:20:39,240 temperature we store there more energy and the kinetic energy of the molecules 764 00:20:39,240 --> 00:20:39,250 and the kinetic energy of the molecules 765 00:20:39,250 --> 00:20:44,539 and the kinetic energy of the molecules increases now suppose that we have a 766 00:20:44,539 --> 00:20:44,549 increases now suppose that we have a 767 00:20:44,549 --> 00:20:49,560 increases now suppose that we have a camera which can take a snapshot and an 768 00:20:49,560 --> 00:20:49,570 camera which can take a snapshot and an 769 00:20:49,570 --> 00:20:53,539 camera which can take a snapshot and an instant time there were short time and 770 00:20:53,539 --> 00:20:53,549 instant time there were short time and 771 00:20:53,549 --> 00:20:57,960 instant time there were short time and sees the molecule right so let's say in 772 00:20:57,960 --> 00:20:57,970 sees the molecule right so let's say in 773 00:20:57,970 --> 00:21:00,659 sees the molecule right so let's say in an instant time just just this is a 774 00:21:00,659 --> 00:21:00,669 an instant time just just this is a 775 00:21:00,669 --> 00:21:04,640 an instant time just just this is a picture just a picture of all of the 776 00:21:04,640 --> 00:21:04,650 picture just a picture of all of the 777 00:21:04,650 --> 00:21:08,039 picture just a picture of all of the molecules there then I will simply have 778 00:21:08,039 --> 00:21:08,049 molecules there then I will simply have 779 00:21:08,049 --> 00:21:15,779 molecules there then I will simply have a distributions that say like this now 780 00:21:15,779 --> 00:21:15,789 a distributions that say like this now 781 00:21:15,789 --> 00:21:18,480 a distributions that say like this now remember all of these are molecules and 782 00:21:18,480 --> 00:21:18,490 remember all of these are molecules and 783 00:21:18,490 --> 00:21:20,490 remember all of these are molecules and they have different plays let's assume 784 00:21:20,490 --> 00:21:20,500 they have different plays let's assume 785 00:21:20,500 --> 00:21:23,430 they have different plays let's assume that this is one picture a snapshot but 786 00:21:23,430 --> 00:21:23,440 that this is one picture a snapshot but 787 00:21:23,440 --> 00:21:27,659 that this is one picture a snapshot but now not only the places but suppose that 788 00:21:27,659 --> 00:21:27,669 now not only the places but suppose that 789 00:21:27,669 --> 00:21:29,640 now not only the places but suppose that this camera also measures the kinetic 790 00:21:29,640 --> 00:21:29,650 this camera also measures the kinetic 791 00:21:29,650 --> 00:21:33,600 this camera also measures the kinetic energy of every molecule right kinetic 792 00:21:33,600 --> 00:21:33,610 energy of every molecule right kinetic 793 00:21:33,610 --> 00:21:35,789 energy of every molecule right kinetic energy of every molecule so we have the 794 00:21:35,789 --> 00:21:35,799 energy of every molecule so we have the 795 00:21:35,799 --> 00:21:41,299 energy of every molecule so we have the kinetic energies actually and directions 796 00:21:41,299 --> 00:21:41,309 kinetic energies actually and directions 797 00:21:41,309 --> 00:21:44,039 kinetic energies actually and directions and kinetic energies that means 1 over 2 798 00:21:44,039 --> 00:21:44,049 and kinetic energies that means 1 over 2 799 00:21:44,049 --> 00:21:47,580 and kinetic energies that means 1 over 2 MV squared on every molecule but the 800 00:21:47,580 --> 00:21:47,590 MV squared on every molecule but the 801 00:21:47,590 --> 00:21:49,200 MV squared on every molecule but the kinetic energy of the molecules will be 802 00:21:49,200 --> 00:21:49,210 kinetic energy of the molecules will be 803 00:21:49,210 --> 00:21:53,930 kinetic energy of the molecules will be different again all different now this 804 00:21:53,930 --> 00:21:53,940 different again all different now this 805 00:21:53,940 --> 00:21:58,250 different again all different now this actually if I can simply take a snapshot 806 00:21:58,250 --> 00:21:58,260 actually if I can simply take a snapshot 807 00:21:58,260 --> 00:22:01,440 actually if I can simply take a snapshot stop the system and determine the 808 00:22:01,440 --> 00:22:01,450 stop the system and determine the 809 00:22:01,450 --> 00:22:06,149 stop the system and determine the positions of the molecule and also their 810 00:22:06,149 --> 00:22:06,159 positions of the molecule and also their 811 00:22:06,159 --> 00:22:11,549 positions of the molecule and also their kinetic energies this will be a 812 00:22:11,549 --> 00:22:11,559 kinetic energies this will be a 813 00:22:11,559 --> 00:22:17,700 kinetic energies this will be a microstate right a microstate now so the 814 00:22:17,700 --> 00:22:17,710 microstate right a microstate now so the 815 00:22:17,710 --> 00:22:23,370 microstate right a microstate now so the microstate actually microstate actually 816 00:22:23,370 --> 00:22:23,380 microstate actually microstate actually 817 00:22:23,380 --> 00:22:26,190 microstate actually microstate actually tells you that just one of the 818 00:22:26,190 --> 00:22:26,200 tells you that just one of the 819 00:22:26,200 --> 00:22:30,419 tells you that just one of the distributions of the molecules in the 820 00:22:30,419 --> 00:22:30,429 distributions of the molecules in the 821 00:22:30,429 --> 00:22:31,290 distributions of the molecules in the space 822 00:22:31,290 --> 00:22:31,300 space 823 00:22:31,300 --> 00:22:33,810 space with their positions and also the 824 00:22:33,810 --> 00:22:33,820 with their positions and also the 825 00:22:33,820 --> 00:22:37,290 with their positions and also the distributions of the kinetic energy to 826 00:22:37,290 --> 00:22:37,300 distributions of the kinetic energy to 827 00:22:37,300 --> 00:22:39,690 distributions of the kinetic energy to the molecules right now suppose that 828 00:22:39,690 --> 00:22:39,700 the molecules right now suppose that 829 00:22:39,700 --> 00:22:43,710 the molecules right now suppose that another instant time you take another 830 00:22:43,710 --> 00:22:43,720 another instant time you take another 831 00:22:43,720 --> 00:22:47,160 another instant time you take another snapshot right and in that snapshot 832 00:22:47,160 --> 00:22:47,170 snapshot right and in that snapshot 833 00:22:47,170 --> 00:22:49,740 snapshot right and in that snapshot let's say you have simply another 834 00:22:49,740 --> 00:22:49,750 let's say you have simply another 835 00:22:49,750 --> 00:22:52,230 let's say you have simply another snapshot here and you have again the 836 00:22:52,230 --> 00:22:52,240 snapshot here and you have again the 837 00:22:52,240 --> 00:22:55,230 snapshot here and you have again the molecules like this remember this is 838 00:22:55,230 --> 00:22:55,240 molecules like this remember this is 839 00:22:55,240 --> 00:22:56,730 molecules like this remember this is Avogadro's number if you're talking 840 00:22:56,730 --> 00:22:56,740 Avogadro's number if you're talking 841 00:22:56,740 --> 00:22:59,780 Avogadro's number if you're talking about one mole of gas now in this case 842 00:22:59,780 --> 00:22:59,790 about one mole of gas now in this case 843 00:22:59,790 --> 00:23:02,700 about one mole of gas now in this case every of those atoms are at different 844 00:23:02,700 --> 00:23:02,710 every of those atoms are at different 845 00:23:02,710 --> 00:23:06,780 every of those atoms are at different place plus their kinetic energies may be 846 00:23:06,780 --> 00:23:06,790 place plus their kinetic energies may be 847 00:23:06,790 --> 00:23:09,120 place plus their kinetic energies may be different because the collusions and so 848 00:23:09,120 --> 00:23:09,130 different because the collusions and so 849 00:23:09,130 --> 00:23:11,970 different because the collusions and so on right may take place so this will 850 00:23:11,970 --> 00:23:11,980 on right may take place so this will 851 00:23:11,980 --> 00:23:14,610 on right may take place so this will simply give you another distribution of 852 00:23:14,610 --> 00:23:14,620 simply give you another distribution of 853 00:23:14,620 --> 00:23:18,900 simply give you another distribution of the molecules with their positions and 854 00:23:18,900 --> 00:23:18,910 the molecules with their positions and 855 00:23:18,910 --> 00:23:21,930 the molecules with their positions and their kinetic energies this is going to 856 00:23:21,930 --> 00:23:21,940 their kinetic energies this is going to 857 00:23:21,940 --> 00:23:29,040 their kinetic energies this is going to be another microstate right now then I 858 00:23:29,040 --> 00:23:29,050 be another microstate right now then I 859 00:23:29,050 --> 00:23:31,770 be another microstate right now then I can take the third forward thought how 860 00:23:31,770 --> 00:23:31,780 can take the third forward thought how 861 00:23:31,780 --> 00:23:38,340 can take the third forward thought how many of those can I find it out hmm very 862 00:23:38,340 --> 00:23:38,350 many of those can I find it out hmm very 863 00:23:38,350 --> 00:23:40,280 many of those can I find it out hmm very not easy 864 00:23:40,280 --> 00:23:40,290 not easy 865 00:23:40,290 --> 00:23:43,380 not easy that's what Boltzmann did actually the 866 00:23:43,380 --> 00:23:43,390 that's what Boltzmann did actually the 867 00:23:43,390 --> 00:23:46,799 that's what Boltzmann did actually the Boltzmann was able to calculate the 868 00:23:46,799 --> 00:23:46,809 Boltzmann was able to calculate the 869 00:23:46,809 --> 00:23:50,060 Boltzmann was able to calculate the number of microstates of 870 00:23:50,060 --> 00:23:50,070 number of microstates of 871 00:23:50,070 --> 00:23:53,940 number of microstates of a system and a given temperatures and 872 00:23:53,940 --> 00:23:53,950 a system and a given temperatures and 873 00:23:53,950 --> 00:24:00,390 a system and a given temperatures and pressure and he find out this this value 874 00:24:00,390 --> 00:24:00,400 pressure and he find out this this value 875 00:24:00,400 --> 00:24:04,830 pressure and he find out this this value here right here this W so that W is 876 00:24:04,830 --> 00:24:04,840 here right here this W so that W is 877 00:24:04,840 --> 00:24:07,919 here right here this W so that W is actually the number of microstates that 878 00:24:07,919 --> 00:24:07,929 actually the number of microstates that 879 00:24:07,929 --> 00:24:11,700 actually the number of microstates that means how many different ways the 880 00:24:11,700 --> 00:24:11,710 means how many different ways the 881 00:24:11,710 --> 00:24:15,000 means how many different ways the molecules can be distributed in space 882 00:24:15,000 --> 00:24:15,010 molecules can be distributed in space 883 00:24:15,010 --> 00:24:18,900 molecules can be distributed in space and with the kinetic energies all of 884 00:24:18,900 --> 00:24:18,910 and with the kinetic energies all of 885 00:24:18,910 --> 00:24:21,110 and with the kinetic energies all of those have different kinetic energies 886 00:24:21,110 --> 00:24:21,120 those have different kinetic energies 887 00:24:21,120 --> 00:24:25,140 those have different kinetic energies right so and that is W that means that 888 00:24:25,140 --> 00:24:25,150 right so and that is W that means that 889 00:24:25,150 --> 00:24:30,090 right so and that is W that means that the larger the number of microstates the 890 00:24:30,090 --> 00:24:30,100 the larger the number of microstates the 891 00:24:30,100 --> 00:24:34,020 the larger the number of microstates the larger will be entropy of the system so 892 00:24:34,020 --> 00:24:34,030 larger will be entropy of the system so 893 00:24:34,030 --> 00:24:36,960 larger will be entropy of the system so the randomness actually will increase 894 00:24:36,960 --> 00:24:36,970 the randomness actually will increase 895 00:24:36,970 --> 00:24:39,900 the randomness actually will increase with the number of microstates and this 896 00:24:39,900 --> 00:24:39,910 with the number of microstates and this 897 00:24:39,910 --> 00:24:42,290 with the number of microstates and this can be calculated this can be calculated 898 00:24:42,290 --> 00:24:42,300 can be calculated this can be calculated 899 00:24:42,300 --> 00:24:44,970 can be calculated this can be calculated but think about again 900 00:24:44,970 --> 00:24:44,980 but think about again 901 00:24:44,980 --> 00:24:49,169 but think about again is positional distributions and the 902 00:24:49,169 --> 00:24:49,179 is positional distributions and the 903 00:24:49,179 --> 00:24:50,640 is positional distributions and the kinetic energy distributions of the 904 00:24:50,640 --> 00:24:50,650 kinetic energy distributions of the 905 00:24:50,650 --> 00:24:52,320 kinetic energy distributions of the molecules at different times you know 906 00:24:52,320 --> 00:24:52,330 molecules at different times you know 907 00:24:52,330 --> 00:24:55,140 molecules at different times you know there's so many but that is that can be 908 00:24:55,140 --> 00:24:55,150 there's so many but that is that can be 909 00:24:55,150 --> 00:24:57,299 there's so many but that is that can be calculated and it's equal to the W 910 00:24:57,299 --> 00:24:57,309 calculated and it's equal to the W 911 00:24:57,309 --> 00:24:59,640 calculated and it's equal to the W Boltzmann said and he said that if I 912 00:24:59,640 --> 00:24:59,650 Boltzmann said and he said that if I 913 00:24:59,650 --> 00:25:02,039 Boltzmann said and he said that if I simply take the logarithm of that 914 00:25:02,039 --> 00:25:02,049 simply take the logarithm of that 915 00:25:02,049 --> 00:25:04,500 simply take the logarithm of that multiplied by the K constant volts my 916 00:25:04,500 --> 00:25:04,510 multiplied by the K constant volts my 917 00:25:04,510 --> 00:25:05,970 multiplied by the K constant volts my constant this is called the Boltzmann 918 00:25:05,970 --> 00:25:05,980 constant this is called the Boltzmann 919 00:25:05,980 --> 00:25:07,289 constant this is called the Boltzmann constant actually okay 920 00:25:07,289 --> 00:25:07,299 constant actually okay 921 00:25:07,299 --> 00:25:10,320 constant actually okay and you get the entropy of the system 922 00:25:10,320 --> 00:25:10,330 and you get the entropy of the system 923 00:25:10,330 --> 00:25:14,549 and you get the entropy of the system entropy Office's you see remember when 924 00:25:14,549 --> 00:25:14,559 entropy Office's you see remember when 925 00:25:14,559 --> 00:25:17,520 entropy Office's you see remember when we talked about the enthalpy of the 926 00:25:17,520 --> 00:25:17,530 we talked about the enthalpy of the 927 00:25:17,530 --> 00:25:21,049 we talked about the enthalpy of the system we said that we can't really 928 00:25:21,049 --> 00:25:21,059 system we said that we can't really 929 00:25:21,059 --> 00:25:24,840 system we said that we can't really measure or calculate the absolute 930 00:25:24,840 --> 00:25:24,850 measure or calculate the absolute 931 00:25:24,850 --> 00:25:29,820 measure or calculate the absolute entropy enthalpy of a system we can't 932 00:25:29,820 --> 00:25:29,830 entropy enthalpy of a system we can't 933 00:25:29,830 --> 00:25:32,850 entropy enthalpy of a system we can't measure the internal energy absolute 934 00:25:32,850 --> 00:25:32,860 measure the internal energy absolute 935 00:25:32,860 --> 00:25:35,490 measure the internal energy absolute total internal energy off the system too 936 00:25:35,490 --> 00:25:35,500 total internal energy off the system too 937 00:25:35,500 --> 00:25:37,770 total internal energy off the system too complicated but what we can really 938 00:25:37,770 --> 00:25:37,780 complicated but what we can really 939 00:25:37,780 --> 00:25:39,990 complicated but what we can really measure we said there we can measure the 940 00:25:39,990 --> 00:25:40,000 measure we said there we can measure the 941 00:25:40,000 --> 00:25:43,169 measure we said there we can measure the change in enthalpy which is Delta H and 942 00:25:43,169 --> 00:25:43,179 change in enthalpy which is Delta H and 943 00:25:43,179 --> 00:25:45,480 change in enthalpy which is Delta H and we can also measure the change in 944 00:25:45,480 --> 00:25:45,490 we can also measure the change in 945 00:25:45,490 --> 00:25:47,909 we can also measure the change in internal energy which is Delta e right 946 00:25:47,909 --> 00:25:47,919 internal energy which is Delta e right 947 00:25:47,919 --> 00:25:51,570 internal energy which is Delta e right capital e but in this case you see we 948 00:25:51,570 --> 00:25:51,580 capital e but in this case you see we 949 00:25:51,580 --> 00:25:56,360 capital e but in this case you see we can actually calculate measure the 950 00:25:56,360 --> 00:25:56,370 can actually calculate measure the 951 00:25:56,370 --> 00:25:59,100 can actually calculate measure the entropy of a system absolute entropy of 952 00:25:59,100 --> 00:25:59,110 entropy of a system absolute entropy of 953 00:25:59,110 --> 00:26:00,960 entropy of a system absolute entropy of a system this is not change this is the 954 00:26:00,960 --> 00:26:00,970 a system this is not change this is the 955 00:26:00,970 --> 00:26:06,090 a system this is not change this is the entropy of the system right now what you 956 00:26:06,090 --> 00:26:06,100 entropy of the system right now what you 957 00:26:06,100 --> 00:26:08,970 entropy of the system right now what you should remember when we talk about macro 958 00:26:08,970 --> 00:26:08,980 should remember when we talk about macro 959 00:26:08,980 --> 00:26:13,530 should remember when we talk about macro macroscopic scale that means macroscopic 960 00:26:13,530 --> 00:26:13,540 macroscopic scale that means macroscopic 961 00:26:13,540 --> 00:26:15,960 macroscopic scale that means macroscopic state which is defined by a temperature 962 00:26:15,960 --> 00:26:15,970 state which is defined by a temperature 963 00:26:15,970 --> 00:26:17,850 state which is defined by a temperature pressure a number of moles volume 964 00:26:17,850 --> 00:26:17,860 pressure a number of moles volume 965 00:26:17,860 --> 00:26:19,980 pressure a number of moles volume whatever those things are for the gases 966 00:26:19,980 --> 00:26:19,990 whatever those things are for the gases 967 00:26:19,990 --> 00:26:25,220 whatever those things are for the gases and this macroscopic state consists of 968 00:26:25,220 --> 00:26:25,230 and this macroscopic state consists of 969 00:26:25,230 --> 00:26:29,940 and this macroscopic state consists of large number of microstates actually 970 00:26:29,940 --> 00:26:29,950 large number of microstates actually 971 00:26:29,950 --> 00:26:33,780 large number of microstates actually right so every macro macroscopic state 972 00:26:33,780 --> 00:26:33,790 right so every macro macroscopic state 973 00:26:33,790 --> 00:26:36,810 right so every macro macroscopic state corresponds to large number of 974 00:26:36,810 --> 00:26:36,820 corresponds to large number of 975 00:26:36,820 --> 00:26:38,280 corresponds to large number of microstates there are a lot of 976 00:26:38,280 --> 00:26:38,290 microstates there are a lot of 977 00:26:38,290 --> 00:26:40,740 microstates there are a lot of microstates like a gas in a container 978 00:26:40,740 --> 00:26:40,750 microstates like a gas in a container 979 00:26:40,750 --> 00:26:42,750 microstates like a gas in a container one liter gas like this you can have 980 00:26:42,750 --> 00:26:42,760 one liter gas like this you can have 981 00:26:42,760 --> 00:26:44,909 one liter gas like this you can have this distributions of kinetic energy at 982 00:26:44,909 --> 00:26:44,919 this distributions of kinetic energy at 983 00:26:44,919 --> 00:26:46,409 this distributions of kinetic energy at position this one that one that one that 984 00:26:46,409 --> 00:26:46,419 position this one that one that one that 985 00:26:46,419 --> 00:26:48,750 position this one that one that one that huge number of those and that can be 986 00:26:48,750 --> 00:26:48,760 huge number of those and that can be 987 00:26:48,760 --> 00:26:51,780 huge number of those and that can be calculated that's equal to W okay now 988 00:26:51,780 --> 00:26:51,790 calculated that's equal to W okay now 989 00:26:51,790 --> 00:26:54,270 calculated that's equal to W okay now again since the entropy is a state 990 00:26:54,270 --> 00:26:54,280 again since the entropy is a state 991 00:26:54,280 --> 00:26:56,580 again since the entropy is a state function the final value minus the 992 00:26:56,580 --> 00:26:56,590 function the final value minus the 993 00:26:56,590 --> 00:26:57,960 function the final value minus the initial value will give the overall 994 00:26:57,960 --> 00:26:57,970 initial value will give the overall 995 00:26:57,970 --> 00:26:59,340 initial value will give the overall change 996 00:26:59,340 --> 00:26:59,350 change 997 00:26:59,350 --> 00:27:02,159 change in this case an increase in the number 998 00:27:02,159 --> 00:27:02,169 in this case an increase in the number 999 00:27:02,169 --> 00:27:03,779 in this case an increase in the number of micro state results in positive 1000 00:27:03,779 --> 00:27:03,789 of micro state results in positive 1001 00:27:03,789 --> 00:27:06,630 of micro state results in positive entropy change and that is simply means 1002 00:27:06,630 --> 00:27:06,640 entropy change and that is simply means 1003 00:27:06,640 --> 00:27:08,789 entropy change and that is simply means that increasing this is important 1004 00:27:08,789 --> 00:27:08,799 that increasing this is important 1005 00:27:08,799 --> 00:27:11,270 that increasing this is important increase in the number of microstates 1006 00:27:11,270 --> 00:27:11,280 increase in the number of microstates 1007 00:27:11,280 --> 00:27:15,360 increase in the number of microstates means higher entropy right higher 1008 00:27:15,360 --> 00:27:15,370 means higher entropy right higher 1009 00:27:15,370 --> 00:27:18,630 means higher entropy right higher entropy and if we calculate the entropy 1010 00:27:18,630 --> 00:27:18,640 entropy and if we calculate the entropy 1011 00:27:18,640 --> 00:27:22,279 entropy and if we calculate the entropy change for from initial to the final 1012 00:27:22,279 --> 00:27:22,289 change for from initial to the final 1013 00:27:22,289 --> 00:27:25,590 change for from initial to the final case then we that will be equals to the 1014 00:27:25,590 --> 00:27:25,600 case then we that will be equals to the 1015 00:27:25,600 --> 00:27:28,799 case then we that will be equals to the entropy of the final system system in 1016 00:27:28,799 --> 00:27:28,809 entropy of the final system system in 1017 00:27:28,809 --> 00:27:30,750 entropy of the final system system in the final state this is the entropy of 1018 00:27:30,750 --> 00:27:30,760 the final state this is the entropy of 1019 00:27:30,760 --> 00:27:32,970 the final state this is the entropy of the system initial state and this will 1020 00:27:32,970 --> 00:27:32,980 the system initial state and this will 1021 00:27:32,980 --> 00:27:35,279 the system initial state and this will be equal to the debt entropy change 1022 00:27:35,279 --> 00:27:35,289 be equal to the debt entropy change 1023 00:27:35,289 --> 00:27:37,560 be equal to the debt entropy change going from initial to the final state 1024 00:27:37,560 --> 00:27:37,570 going from initial to the final state 1025 00:27:37,570 --> 00:27:41,340 going from initial to the final state again based on the number of microstates 1026 00:27:41,340 --> 00:27:41,350 again based on the number of microstates 1027 00:27:41,350 --> 00:27:44,760 again based on the number of microstates that the system has right the number of 1028 00:27:44,760 --> 00:27:44,770 that the system has right the number of 1029 00:27:44,770 --> 00:27:49,940 that the system has right the number of microstates now let's look at how the 1030 00:27:49,940 --> 00:27:49,950 microstates now let's look at how the 1031 00:27:49,950 --> 00:27:53,070 microstates now let's look at how the volume and temperature change on the 1032 00:27:53,070 --> 00:27:53,080 volume and temperature change on the 1033 00:27:53,080 --> 00:27:56,460 volume and temperature change on the system affects the entropy we can follow 1034 00:27:56,460 --> 00:27:56,470 system affects the entropy we can follow 1035 00:27:56,470 --> 00:27:58,620 system affects the entropy we can follow it again if you increase the volume 1036 00:27:58,620 --> 00:27:58,630 it again if you increase the volume 1037 00:27:58,630 --> 00:28:01,169 it again if you increase the volume there are more positions possible for 1038 00:28:01,169 --> 00:28:01,179 there are more positions possible for 1039 00:28:01,179 --> 00:28:03,289 there are more positions possible for the molecules this results in more 1040 00:28:03,289 --> 00:28:03,299 the molecules this results in more 1041 00:28:03,299 --> 00:28:06,720 the molecules this results in more microstates so increased entropy that 1042 00:28:06,720 --> 00:28:06,730 microstates so increased entropy that 1043 00:28:06,730 --> 00:28:10,590 microstates so increased entropy that means if I put that 1 mole of gas not in 1044 00:28:10,590 --> 00:28:10,600 means if I put that 1 mole of gas not in 1045 00:28:10,600 --> 00:28:13,279 means if I put that 1 mole of gas not in this container let's say this is like 24 1046 00:28:13,279 --> 00:28:13,289 this container let's say this is like 24 1047 00:28:13,289 --> 00:28:15,990 this container let's say this is like 24 liters suppose that I put it in 30 1048 00:28:15,990 --> 00:28:16,000 liters suppose that I put it in 30 1049 00:28:16,000 --> 00:28:18,120 liters suppose that I put it in 30 liters what does that means I will have 1050 00:28:18,120 --> 00:28:18,130 liters what does that means I will have 1051 00:28:18,130 --> 00:28:20,730 liters what does that means I will have more space more space means that there 1052 00:28:20,730 --> 00:28:20,740 more space more space means that there 1053 00:28:20,740 --> 00:28:23,779 more space more space means that there will be more possible microstates 1054 00:28:23,779 --> 00:28:23,789 will be more possible microstates 1055 00:28:23,789 --> 00:28:27,419 will be more possible microstates actually for the system and increase in 1056 00:28:27,419 --> 00:28:27,429 actually for the system and increase in 1057 00:28:27,429 --> 00:28:29,399 actually for the system and increase in the number of microstates means that the 1058 00:28:29,399 --> 00:28:29,409 the number of microstates means that the 1059 00:28:29,409 --> 00:28:31,620 the number of microstates means that the entropy will increase so if you increase 1060 00:28:31,620 --> 00:28:31,630 entropy will increase so if you increase 1061 00:28:31,630 --> 00:28:34,890 entropy will increase so if you increase the volume of a gas entropy increases 1062 00:28:34,890 --> 00:28:34,900 the volume of a gas entropy increases 1063 00:28:34,900 --> 00:28:38,159 the volume of a gas entropy increases right increases now if you increase the 1064 00:28:38,159 --> 00:28:38,169 right increases now if you increase the 1065 00:28:38,169 --> 00:28:40,470 right increases now if you increase the temperature the average kinetic energy 1066 00:28:40,470 --> 00:28:40,480 temperature the average kinetic energy 1067 00:28:40,480 --> 00:28:44,789 temperature the average kinetic energy increases and also the the broadness of 1068 00:28:44,789 --> 00:28:44,799 increases and also the the broadness of 1069 00:28:44,799 --> 00:28:47,640 increases and also the the broadness of the kinetic energy of the molecule 1070 00:28:47,640 --> 00:28:47,650 the kinetic energy of the molecule 1071 00:28:47,650 --> 00:28:50,190 the kinetic energy of the molecule increases to remember the increase in 1072 00:28:50,190 --> 00:28:50,200 increases to remember the increase in 1073 00:28:50,200 --> 00:28:52,289 increases to remember the increase in the temperature the shape of the kinetic 1074 00:28:52,289 --> 00:28:52,299 the temperature the shape of the kinetic 1075 00:28:52,299 --> 00:28:54,899 the temperature the shape of the kinetic energy distributions like this and what 1076 00:28:54,899 --> 00:28:54,909 energy distributions like this and what 1077 00:28:54,909 --> 00:28:57,240 energy distributions like this and what does that mean that means again that the 1078 00:28:57,240 --> 00:28:57,250 does that mean that means again that the 1079 00:28:57,250 --> 00:28:59,549 does that mean that means again that the possible number of microstates that 1080 00:28:59,549 --> 00:28:59,559 possible number of microstates that 1081 00:28:59,559 --> 00:29:01,649 possible number of microstates that means the molecules have been different 1082 00:29:01,649 --> 00:29:01,659 means the molecules have been different 1083 00:29:01,659 --> 00:29:04,860 means the molecules have been different kinetic energies will increase and that 1084 00:29:04,860 --> 00:29:04,870 kinetic energies will increase and that 1085 00:29:04,870 --> 00:29:07,649 kinetic energies will increase and that will also increase the entropy of the 1086 00:29:07,649 --> 00:29:07,659 will also increase the entropy of the 1087 00:29:07,659 --> 00:29:09,780 will also increase the entropy of the system so average kinetic energy 1088 00:29:09,780 --> 00:29:09,790 system so average kinetic energy 1089 00:29:09,790 --> 00:29:12,270 system so average kinetic energy increase this result in greater 1090 00:29:12,270 --> 00:29:12,280 increase this result in greater 1091 00:29:12,280 --> 00:29:14,520 increase this result in greater tribunal of molecular speeds that's 1092 00:29:14,520 --> 00:29:14,530 tribunal of molecular speeds that's 1093 00:29:14,530 --> 00:29:15,270 tribunal of molecular speeds that's important 1094 00:29:15,270 --> 00:29:15,280 important 1095 00:29:15,280 --> 00:29:18,660 important that means more microstates right more 1096 00:29:18,660 --> 00:29:18,670 that means more microstates right more 1097 00:29:18,670 --> 00:29:22,830 that means more microstates right more microstates and therefore there are more 1098 00:29:22,830 --> 00:29:22,840 microstates and therefore there are more 1099 00:29:22,840 --> 00:29:24,960 microstates and therefore there are more possible kinetic energy values resulted 1100 00:29:24,960 --> 00:29:24,970 possible kinetic energy values resulted 1101 00:29:24,970 --> 00:29:27,240 possible kinetic energy values resulted in more microstates increase in entropy 1102 00:29:27,240 --> 00:29:27,250 in more microstates increase in entropy 1103 00:29:27,250 --> 00:29:29,520 in more microstates increase in entropy what does that means increasing the 1104 00:29:29,520 --> 00:29:29,530 what does that means increasing the 1105 00:29:29,530 --> 00:29:32,190 what does that means increasing the temperature of gas will always increases 1106 00:29:32,190 --> 00:29:32,200 temperature of gas will always increases 1107 00:29:32,200 --> 00:29:35,370 temperature of gas will always increases the entropy of the system entropy of the 1108 00:29:35,370 --> 00:29:35,380 the entropy of the system entropy of the 1109 00:29:35,380 --> 00:29:42,240 the entropy of the system entropy of the system now how about the if I increase 1110 00:29:42,240 --> 00:29:42,250 system now how about the if I increase 1111 00:29:42,250 --> 00:29:45,890 system now how about the if I increase the number of moles of gas 1112 00:29:45,890 --> 00:29:45,900 the number of moles of gas 1113 00:29:45,900 --> 00:29:48,330 the number of moles of gas instead of like one mole if I put here 1114 00:29:48,330 --> 00:29:48,340 instead of like one mole if I put here 1115 00:29:48,340 --> 00:29:53,580 instead of like one mole if I put here one point two moles of gas how that will 1116 00:29:53,580 --> 00:29:53,590 one point two moles of gas how that will 1117 00:29:53,590 --> 00:29:55,550 one point two moles of gas how that will affect the entropy of the system 1118 00:29:55,550 --> 00:29:55,560 affect the entropy of the system 1119 00:29:55,560 --> 00:29:58,290 affect the entropy of the system increased definitely if you increase the 1120 00:29:58,290 --> 00:29:58,300 increased definitely if you increase the 1121 00:29:58,300 --> 00:30:00,780 increased definitely if you increase the number of particles molecules than you 1122 00:30:00,780 --> 00:30:00,790 number of particles molecules than you 1123 00:30:00,790 --> 00:30:01,980 number of particles molecules than you increase the number of microstates 1124 00:30:01,980 --> 00:30:01,990 increase the number of microstates 1125 00:30:01,990 --> 00:30:04,230 increase the number of microstates definitely and that will increase the 1126 00:30:04,230 --> 00:30:04,240 definitely and that will increase the 1127 00:30:04,240 --> 00:30:08,670 definitely and that will increase the entropy of the system again now the 1128 00:30:08,670 --> 00:30:08,680 entropy of the system again now the 1129 00:30:08,680 --> 00:30:12,660 entropy of the system again now the energy is simply stored in the molecules 1130 00:30:12,660 --> 00:30:12,670 energy is simply stored in the molecules 1131 00:30:12,670 --> 00:30:17,460 energy is simply stored in the molecules in three different ways right I should 1132 00:30:17,460 --> 00:30:17,470 in three different ways right I should 1133 00:30:17,470 --> 00:30:22,680 in three different ways right I should say form one is the translational energy 1134 00:30:22,680 --> 00:30:22,690 say form one is the translational energy 1135 00:30:22,690 --> 00:30:26,660 say form one is the translational energy of the molecules and these are simply 1136 00:30:26,660 --> 00:30:26,670 of the molecules and these are simply 1137 00:30:26,670 --> 00:30:30,450 of the molecules and these are simply due to the motions of the molecules this 1138 00:30:30,450 --> 00:30:30,460 due to the motions of the molecules this 1139 00:30:30,460 --> 00:30:31,920 due to the motions of the molecules this is actually the kinetic energy movement 1140 00:30:31,920 --> 00:30:31,930 is actually the kinetic energy movement 1141 00:30:31,930 --> 00:30:34,080 is actually the kinetic energy movement of the entire molecule from one place in 1142 00:30:34,080 --> 00:30:34,090 of the entire molecule from one place in 1143 00:30:34,090 --> 00:30:36,360 of the entire molecule from one place in other this is a translational energy and 1144 00:30:36,360 --> 00:30:36,370 other this is a translational energy and 1145 00:30:36,370 --> 00:30:38,070 other this is a translational energy and it's corresponds to the kinetic energy 1146 00:30:38,070 --> 00:30:38,080 it's corresponds to the kinetic energy 1147 00:30:38,080 --> 00:30:42,290 it's corresponds to the kinetic energy now the vibrational energy and that is 1148 00:30:42,290 --> 00:30:42,300 now the vibrational energy and that is 1149 00:30:42,300 --> 00:30:44,850 now the vibrational energy and that is periodic motions of the atoms within a 1150 00:30:44,850 --> 00:30:44,860 periodic motions of the atoms within a 1151 00:30:44,860 --> 00:30:47,160 periodic motions of the atoms within a molecule that means at a certain 1152 00:30:47,160 --> 00:30:47,170 molecule that means at a certain 1153 00:30:47,170 --> 00:30:49,470 molecule that means at a certain temperature if you have molecules made 1154 00:30:49,470 --> 00:30:49,480 temperature if you have molecules made 1155 00:30:49,480 --> 00:30:51,990 temperature if you have molecules made of two atoms for example then these two 1156 00:30:51,990 --> 00:30:52,000 of two atoms for example then these two 1157 00:30:52,000 --> 00:30:54,260 of two atoms for example then these two atoms makes this kind of motions and 1158 00:30:54,260 --> 00:30:54,270 atoms makes this kind of motions and 1159 00:30:54,270 --> 00:30:56,880 atoms makes this kind of motions and this is called vibrational motion and 1160 00:30:56,880 --> 00:30:56,890 this is called vibrational motion and 1161 00:30:56,890 --> 00:30:59,280 this is called vibrational motion and this vibrational motion corresponds to 1162 00:30:59,280 --> 00:30:59,290 this vibrational motion corresponds to 1163 00:30:59,290 --> 00:31:02,370 this vibrational motion corresponds to an energy so the energy is stored in the 1164 00:31:02,370 --> 00:31:02,380 an energy so the energy is stored in the 1165 00:31:02,380 --> 00:31:04,620 an energy so the energy is stored in the form of translational energy or in the 1166 00:31:04,620 --> 00:31:04,630 form of translational energy or in the 1167 00:31:04,630 --> 00:31:08,280 form of translational energy or in the form of vibrational energy now if you 1168 00:31:08,280 --> 00:31:08,290 form of vibrational energy now if you 1169 00:31:08,290 --> 00:31:10,680 form of vibrational energy now if you have simply molecules made of three 1170 00:31:10,680 --> 00:31:10,690 have simply molecules made of three 1171 00:31:10,690 --> 00:31:14,100 have simply molecules made of three atoms then the number of different 1172 00:31:14,100 --> 00:31:14,110 atoms then the number of different 1173 00:31:14,110 --> 00:31:17,070 atoms then the number of different vibrational energies or vibrational 1174 00:31:17,070 --> 00:31:17,080 vibrational energies or vibrational 1175 00:31:17,080 --> 00:31:21,720 vibrational energies or vibrational motions will be more than the two atom 1176 00:31:21,720 --> 00:31:21,730 motions will be more than the two atom 1177 00:31:21,730 --> 00:31:25,830 motions will be more than the two atom or die molecular species so 1178 00:31:25,830 --> 00:31:25,840 or die molecular species so 1179 00:31:25,840 --> 00:31:28,740 or die molecular species so again as the number of atom increases in 1180 00:31:28,740 --> 00:31:28,750 again as the number of atom increases in 1181 00:31:28,750 --> 00:31:32,789 again as the number of atom increases in the molecule then we rotate the 1182 00:31:32,789 --> 00:31:32,799 the molecule then we rotate the 1183 00:31:32,799 --> 00:31:35,430 the molecule then we rotate the vibrational energy that stored there 1184 00:31:35,430 --> 00:31:35,440 vibrational energy that stored there 1185 00:31:35,440 --> 00:31:40,260 vibrational energy that stored there also increases to now rotational energy 1186 00:31:40,260 --> 00:31:40,270 also increases to now rotational energy 1187 00:31:40,270 --> 00:31:43,049 also increases to now rotational energy that means corresponds to the rotation 1188 00:31:43,049 --> 00:31:43,059 that means corresponds to the rotation 1189 00:31:43,059 --> 00:31:46,080 that means corresponds to the rotation of the molecule around an axis which 1190 00:31:46,080 --> 00:31:46,090 of the molecule around an axis which 1191 00:31:46,090 --> 00:31:49,380 of the molecule around an axis which axes this may be an X Y or z axis so 1192 00:31:49,380 --> 00:31:49,390 axes this may be an X Y or z axis so 1193 00:31:49,390 --> 00:31:50,909 axes this may be an X Y or z axis so there are three different forms of 1194 00:31:50,909 --> 00:31:50,919 there are three different forms of 1195 00:31:50,919 --> 00:31:55,350 there are three different forms of rotational energy - so on so again here 1196 00:31:55,350 --> 00:31:55,360 rotational energy - so on so again here 1197 00:31:55,360 --> 00:31:57,180 rotational energy - so on so again here it says more atoms means more 1198 00:31:57,180 --> 00:31:57,190 it says more atoms means more 1199 00:31:57,190 --> 00:31:59,760 it says more atoms means more microstates more possible molecular 1200 00:31:59,760 --> 00:31:59,770 microstates more possible molecular 1201 00:31:59,770 --> 00:32:03,210 microstates more possible molecular motions again means higher entropy 1202 00:32:03,210 --> 00:32:03,220 motions again means higher entropy 1203 00:32:03,220 --> 00:32:06,810 motions again means higher entropy higher entropy right so here the example 1204 00:32:06,810 --> 00:32:06,820 higher entropy right so here the example 1205 00:32:06,820 --> 00:32:08,789 higher entropy right so here the example this is the water molecule these three 1206 00:32:08,789 --> 00:32:08,799 this is the water molecule these three 1207 00:32:08,799 --> 00:32:12,450 this is the water molecule these three are vibrational motions again this for 1208 00:32:12,450 --> 00:32:12,460 are vibrational motions again this for 1209 00:32:12,460 --> 00:32:14,820 are vibrational motions again this for example corresponds that at the same 1210 00:32:14,820 --> 00:32:14,830 example corresponds that at the same 1211 00:32:14,830 --> 00:32:20,460 example corresponds that at the same time these two atoms are getting away 1212 00:32:20,460 --> 00:32:20,470 time these two atoms are getting away 1213 00:32:20,470 --> 00:32:22,620 time these two atoms are getting away from each other and also moving to each 1214 00:32:22,620 --> 00:32:22,630 from each other and also moving to each 1215 00:32:22,630 --> 00:32:25,470 from each other and also moving to each other closer away closer away and so on 1216 00:32:25,470 --> 00:32:25,480 other closer away closer away and so on 1217 00:32:25,480 --> 00:32:27,240 other closer away closer away and so on and this does the same kind of things 1218 00:32:27,240 --> 00:32:27,250 and this does the same kind of things 1219 00:32:27,250 --> 00:32:29,700 and this does the same kind of things you know up and down both of those now 1220 00:32:29,700 --> 00:32:29,710 you know up and down both of those now 1221 00:32:29,710 --> 00:32:32,730 you know up and down both of those now this is again this angle changes opens 1222 00:32:32,730 --> 00:32:32,740 this is again this angle changes opens 1223 00:32:32,740 --> 00:32:35,820 this is again this angle changes opens up and closes opens closes periodically 1224 00:32:35,820 --> 00:32:35,830 up and closes opens closes periodically 1225 00:32:35,830 --> 00:32:38,220 up and closes opens closes periodically actually and this one is another 1226 00:32:38,220 --> 00:32:38,230 actually and this one is another 1227 00:32:38,230 --> 00:32:40,019 actually and this one is another vibration motions this is called the 1228 00:32:40,019 --> 00:32:40,029 vibration motions this is called the 1229 00:32:40,029 --> 00:32:41,669 vibration motions this is called the symmetric vibration motion this is 1230 00:32:41,669 --> 00:32:41,679 symmetric vibration motion this is 1231 00:32:41,679 --> 00:32:44,159 symmetric vibration motion this is anti-symmetric that means as this atom 1232 00:32:44,159 --> 00:32:44,169 anti-symmetric that means as this atom 1233 00:32:44,169 --> 00:32:46,139 anti-symmetric that means as this atom simply moves in this direction that 1234 00:32:46,139 --> 00:32:46,149 simply moves in this direction that 1235 00:32:46,149 --> 00:32:48,360 simply moves in this direction that atoms goes in there as this atom goes 1236 00:32:48,360 --> 00:32:48,370 atoms goes in there as this atom goes 1237 00:32:48,370 --> 00:32:53,120 atoms goes in there as this atom goes out this item goes out in that is 1238 00:32:53,120 --> 00:32:53,130 1239 00:32:53,130 --> 00:32:55,710 unsymmetrical vibration motions so all 1240 00:32:55,710 --> 00:32:55,720 unsymmetrical vibration motions so all 1241 00:32:55,720 --> 00:33:00,690 unsymmetrical vibration motions so all of these kind of motions stores the 1242 00:33:00,690 --> 00:33:00,700 of these kind of motions stores the 1243 00:33:00,700 --> 00:33:06,539 of these kind of motions stores the energies there right energies there now 1244 00:33:06,539 --> 00:33:06,549 energies there right energies there now 1245 00:33:06,549 --> 00:33:10,590 energies there right energies there now entropy on a molecular scale again the 1246 00:33:10,590 --> 00:33:10,600 entropy on a molecular scale again the 1247 00:33:10,600 --> 00:33:13,350 entropy on a molecular scale again the number of microstates therefore and the 1248 00:33:13,350 --> 00:33:13,360 number of microstates therefore and the 1249 00:33:13,360 --> 00:33:15,539 number of microstates therefore and the entropy tend to increase with increase 1250 00:33:15,539 --> 00:33:15,549 entropy tend to increase with increase 1251 00:33:15,549 --> 00:33:19,019 entropy tend to increase with increase in this is again sort of the result 1252 00:33:19,019 --> 00:33:19,029 in this is again sort of the result 1253 00:33:19,029 --> 00:33:22,320 in this is again sort of the result conclusion with temperature increase in 1254 00:33:22,320 --> 00:33:22,330 conclusion with temperature increase in 1255 00:33:22,330 --> 00:33:24,240 conclusion with temperature increase in volume increase in the number of 1256 00:33:24,240 --> 00:33:24,250 volume increase in the number of 1257 00:33:24,250 --> 00:33:25,980 volume increase in the number of independent moving particles if you 1258 00:33:25,980 --> 00:33:25,990 independent moving particles if you 1259 00:33:25,990 --> 00:33:27,930 independent moving particles if you consider the gas increase in the 1260 00:33:27,930 --> 00:33:27,940 consider the gas increase in the 1261 00:33:27,940 --> 00:33:28,919 consider the gas increase in the temperature increase in the volume 1262 00:33:28,919 --> 00:33:28,929 temperature increase in the volume 1263 00:33:28,929 --> 00:33:31,320 temperature increase in the volume increase in the number of moles of gas 1264 00:33:31,320 --> 00:33:31,330 increase in the number of moles of gas 1265 00:33:31,330 --> 00:33:33,330 increase in the number of moles of gas always increases the number of 1266 00:33:33,330 --> 00:33:33,340 always increases the number of 1267 00:33:33,340 --> 00:33:34,889 always increases the number of microstates increase in number of 1268 00:33:34,889 --> 00:33:34,899 microstates increase in number of 1269 00:33:34,899 --> 00:33:36,899 microstates increase in number of microstates means increase in the 1270 00:33:36,899 --> 00:33:36,909 microstates means increase in the 1271 00:33:36,909 --> 00:33:39,480 microstates means increase in the entropy you see again the end 1272 00:33:39,480 --> 00:33:39,490 entropy you see again the end 1273 00:33:39,490 --> 00:33:43,140 entropy you see again the end Trippi of the system is determined by 1274 00:33:43,140 --> 00:33:43,150 Trippi of the system is determined by 1275 00:33:43,150 --> 00:33:48,200 Trippi of the system is determined by the number of microstates that are 1276 00:33:48,200 --> 00:33:48,210 the number of microstates that are 1277 00:33:48,210 --> 00:33:50,910 the number of microstates that are present in that system right number of 1278 00:33:50,910 --> 00:33:50,920 present in that system right number of 1279 00:33:50,920 --> 00:33:57,720 present in that system right number of microstates now and how the entropy and 1280 00:33:57,720 --> 00:33:57,730 microstates now and how the entropy and 1281 00:33:57,730 --> 00:33:59,430 microstates now and how the entropy and the physical states are related you can 1282 00:33:59,430 --> 00:33:59,440 the physical states are related you can 1283 00:33:59,440 --> 00:34:02,370 the physical states are related you can easily guess this again entropy 1284 00:34:02,370 --> 00:34:02,380 easily guess this again entropy 1285 00:34:02,380 --> 00:34:04,140 easily guess this again entropy increases with the freedom of the 1286 00:34:04,140 --> 00:34:04,150 increases with the freedom of the 1287 00:34:04,150 --> 00:34:07,110 increases with the freedom of the motions of the molecules certainly if 1288 00:34:07,110 --> 00:34:07,120 motions of the molecules certainly if 1289 00:34:07,120 --> 00:34:10,500 motions of the molecules certainly if they move more freely and for example if 1290 00:34:10,500 --> 00:34:10,510 they move more freely and for example if 1291 00:34:10,510 --> 00:34:14,909 they move more freely and for example if you go from gas to the liquid to the 1292 00:34:14,909 --> 00:34:14,919 you go from gas to the liquid to the 1293 00:34:14,919 --> 00:34:19,280 you go from gas to the liquid to the solid suppose that you have one mole of 1294 00:34:19,280 --> 00:34:19,290 solid suppose that you have one mole of 1295 00:34:19,290 --> 00:34:23,970 solid suppose that you have one mole of gas water and then one mole of liquid 1296 00:34:23,970 --> 00:34:23,980 gas water and then one mole of liquid 1297 00:34:23,980 --> 00:34:28,080 gas water and then one mole of liquid water and one mole of solid water if I 1298 00:34:28,080 --> 00:34:28,090 water and one mole of solid water if I 1299 00:34:28,090 --> 00:34:31,350 water and one mole of solid water if I ask you which one will have the highest 1300 00:34:31,350 --> 00:34:31,360 ask you which one will have the highest 1301 00:34:31,360 --> 00:34:35,909 ask you which one will have the highest entropy definitely the gas right and 1302 00:34:35,909 --> 00:34:35,919 entropy definitely the gas right and 1303 00:34:35,919 --> 00:34:39,960 entropy definitely the gas right and then next one is we simply liquid and 1304 00:34:39,960 --> 00:34:39,970 then next one is we simply liquid and 1305 00:34:39,970 --> 00:34:42,810 then next one is we simply liquid and the other one is the solid so this is 1306 00:34:42,810 --> 00:34:42,820 the other one is the solid so this is 1307 00:34:42,820 --> 00:34:44,609 the other one is the solid so this is again yeah because the freedom of 1308 00:34:44,609 --> 00:34:44,619 again yeah because the freedom of 1309 00:34:44,619 --> 00:34:46,980 again yeah because the freedom of motions of the molecules is largest in 1310 00:34:46,980 --> 00:34:46,990 motions of the molecules is largest in 1311 00:34:46,990 --> 00:34:50,490 motions of the molecules is largest in the gas then less in the liquid and very 1312 00:34:50,490 --> 00:34:50,500 the gas then less in the liquid and very 1313 00:34:50,500 --> 00:34:53,340 the gas then less in the liquid and very confined in the solid actually in the 1314 00:34:53,340 --> 00:34:53,350 confined in the solid actually in the 1315 00:34:53,350 --> 00:34:55,680 confined in the solid actually in the solid we only have vibrational rather 1316 00:34:55,680 --> 00:34:55,690 solid we only have vibrational rather 1317 00:34:55,690 --> 00:34:57,990 solid we only have vibrational rather than with translational no translation 1318 00:34:57,990 --> 00:34:58,000 than with translational no translation 1319 00:34:58,000 --> 00:35:00,810 than with translational no translation only vibrational and rotational only 1320 00:35:00,810 --> 00:35:00,820 only vibrational and rotational only 1321 00:35:00,820 --> 00:35:02,880 only vibrational and rotational only actually or even no rotational but in 1322 00:35:02,880 --> 00:35:02,890 actually or even no rotational but in 1323 00:35:02,890 --> 00:35:05,690 actually or even no rotational but in the liquid we have simply translational 1324 00:35:05,690 --> 00:35:05,700 the liquid we have simply translational 1325 00:35:05,700 --> 00:35:09,570 the liquid we have simply translational rotational and vibrational all of those 1326 00:35:09,570 --> 00:35:09,580 rotational and vibrational all of those 1327 00:35:09,580 --> 00:35:12,690 rotational and vibrational all of those are there as a matter of fact so the 1328 00:35:12,690 --> 00:35:12,700 are there as a matter of fact so the 1329 00:35:12,700 --> 00:35:16,380 are there as a matter of fact so the entropy decreases going from gas state 1330 00:35:16,380 --> 00:35:16,390 entropy decreases going from gas state 1331 00:35:16,390 --> 00:35:18,930 entropy decreases going from gas state to the solid and increases going from 1332 00:35:18,930 --> 00:35:18,940 to the solid and increases going from 1333 00:35:18,940 --> 00:35:21,420 to the solid and increases going from solid to the gas gas liquid and so on 1334 00:35:21,420 --> 00:35:21,430 solid to the gas gas liquid and so on 1335 00:35:21,430 --> 00:35:24,420 solid to the gas gas liquid and so on entropy increases for four processes 1336 00:35:24,420 --> 00:35:24,430 entropy increases for four processes 1337 00:35:24,430 --> 00:35:26,940 entropy increases for four processes where the gas formed from either solids 1338 00:35:26,940 --> 00:35:26,950 where the gas formed from either solids 1339 00:35:26,950 --> 00:35:29,609 where the gas formed from either solids or liquids that means this is the first 1340 00:35:29,609 --> 00:35:29,619 or liquids that means this is the first 1341 00:35:29,619 --> 00:35:33,359 or liquids that means this is the first one it says simply if a chemical 1342 00:35:33,359 --> 00:35:33,369 one it says simply if a chemical 1343 00:35:33,369 --> 00:35:37,830 one it says simply if a chemical reaction or in a process gas forms from 1344 00:35:37,830 --> 00:35:37,840 reaction or in a process gas forms from 1345 00:35:37,840 --> 00:35:41,010 reaction or in a process gas forms from the solids or liquids the entropy 1346 00:35:41,010 --> 00:35:41,020 the solids or liquids the entropy 1347 00:35:41,020 --> 00:35:43,910 the solids or liquids the entropy increases right entropy will increase 1348 00:35:43,910 --> 00:35:43,920 increases right entropy will increase 1349 00:35:43,920 --> 00:35:47,580 increases right entropy will increase liquids or solution form from solids 1350 00:35:47,580 --> 00:35:47,590 liquids or solution form from solids 1351 00:35:47,590 --> 00:35:51,480 liquids or solution form from solids this is simply means that the mountain 1352 00:35:51,480 --> 00:35:51,490 this is simply means that the mountain 1353 00:35:51,490 --> 00:35:53,160 this is simply means that the mountain of the solids and 1354 00:35:53,160 --> 00:35:53,170 of the solids and 1355 00:35:53,170 --> 00:35:55,440 of the solids and that entropy again increases as the 1356 00:35:55,440 --> 00:35:55,450 that entropy again increases as the 1357 00:35:55,450 --> 00:35:57,180 that entropy again increases as the number of gas molecule increases during 1358 00:35:57,180 --> 00:35:57,190 number of gas molecule increases during 1359 00:35:57,190 --> 00:35:58,920 number of gas molecule increases during a chemical reaction if you dealing with 1360 00:35:58,920 --> 00:35:58,930 a chemical reaction if you dealing with 1361 00:35:58,930 --> 00:36:00,720 a chemical reaction if you dealing with the chemical reaction entropy is also 1362 00:36:00,720 --> 00:36:00,730 the chemical reaction entropy is also 1363 00:36:00,730 --> 00:36:03,030 the chemical reaction entropy is also increasing for example here is the 1364 00:36:03,030 --> 00:36:03,040 increasing for example here is the 1365 00:36:03,040 --> 00:36:04,920 increasing for example here is the chemical reaction example nitrogen 1366 00:36:04,920 --> 00:36:04,930 chemical reaction example nitrogen 1367 00:36:04,930 --> 00:36:07,530 chemical reaction example nitrogen monoxide reacting with the oxygen to 1368 00:36:07,530 --> 00:36:07,540 monoxide reacting with the oxygen to 1369 00:36:07,540 --> 00:36:10,470 monoxide reacting with the oxygen to form nitrogen dioxide right so in this 1370 00:36:10,470 --> 00:36:10,480 form nitrogen dioxide right so in this 1371 00:36:10,480 --> 00:36:13,500 form nitrogen dioxide right so in this reaction will the entropy of the system 1372 00:36:13,500 --> 00:36:13,510 reaction will the entropy of the system 1373 00:36:13,510 --> 00:36:16,260 reaction will the entropy of the system will increase or decrease we will look 1374 00:36:16,260 --> 00:36:16,270 will increase or decrease we will look 1375 00:36:16,270 --> 00:36:19,230 will increase or decrease we will look at the number of gas molecules number of 1376 00:36:19,230 --> 00:36:19,240 at the number of gas molecules number of 1377 00:36:19,240 --> 00:36:22,620 at the number of gas molecules number of gas molecules so we have simply three 1378 00:36:22,620 --> 00:36:22,630 gas molecules so we have simply three 1379 00:36:22,630 --> 00:36:25,020 gas molecules so we have simply three gas molecules in the reactant side and 1380 00:36:25,020 --> 00:36:25,030 gas molecules in the reactant side and 1381 00:36:25,030 --> 00:36:27,210 gas molecules in the reactant side and we have two gas molecules on the product 1382 00:36:27,210 --> 00:36:27,220 we have two gas molecules on the product 1383 00:36:27,220 --> 00:36:28,650 we have two gas molecules on the product side what does that means that means 1384 00:36:28,650 --> 00:36:28,660 side what does that means that means 1385 00:36:28,660 --> 00:36:31,260 side what does that means that means three gas molecules our reactant to form 1386 00:36:31,260 --> 00:36:31,270 three gas molecules our reactant to form 1387 00:36:31,270 --> 00:36:33,359 three gas molecules our reactant to form two gas molecules means the number of 1388 00:36:33,359 --> 00:36:33,369 two gas molecules means the number of 1389 00:36:33,369 --> 00:36:36,030 two gas molecules means the number of gas molecules decreasing means the 1390 00:36:36,030 --> 00:36:36,040 gas molecules decreasing means the 1391 00:36:36,040 --> 00:36:39,240 gas molecules decreasing means the entropy decreases so Delta s actually 1392 00:36:39,240 --> 00:36:39,250 entropy decreases so Delta s actually 1393 00:36:39,250 --> 00:36:42,000 entropy decreases so Delta s actually for this reaction will be negative means 1394 00:36:42,000 --> 00:36:42,010 for this reaction will be negative means 1395 00:36:42,010 --> 00:36:44,280 for this reaction will be negative means that the entropy of the system decreases 1396 00:36:44,280 --> 00:36:44,290 that the entropy of the system decreases 1397 00:36:44,290 --> 00:36:46,530 that the entropy of the system decreases as a matter of fact so qualitatively we 1398 00:36:46,530 --> 00:36:46,540 as a matter of fact so qualitatively we 1399 00:36:46,540 --> 00:36:48,839 as a matter of fact so qualitatively we can easily guess whether the entropy in 1400 00:36:48,839 --> 00:36:48,849 can easily guess whether the entropy in 1401 00:36:48,849 --> 00:36:50,960 can easily guess whether the entropy in a process or a chemical reaction 1402 00:36:50,960 --> 00:36:50,970 a process or a chemical reaction 1403 00:36:50,970 --> 00:36:54,510 a process or a chemical reaction decreases or increases as a matter of 1404 00:36:54,510 --> 00:36:54,520 decreases or increases as a matter of 1405 00:36:54,520 --> 00:36:57,359 decreases or increases as a matter of fact now here that's the point here is 1406 00:36:57,359 --> 00:36:57,369 fact now here that's the point here is 1407 00:36:57,369 --> 00:37:02,609 fact now here that's the point here is again we said the entropy particularly 1408 00:37:02,609 --> 00:37:02,619 again we said the entropy particularly 1409 00:37:02,619 --> 00:37:05,069 again we said the entropy particularly off a system increases with increase in 1410 00:37:05,069 --> 00:37:05,079 off a system increases with increase in 1411 00:37:05,079 --> 00:37:08,880 off a system increases with increase in temperature increase in volume if it's a 1412 00:37:08,880 --> 00:37:08,890 temperature increase in volume if it's a 1413 00:37:08,890 --> 00:37:11,490 temperature increase in volume if it's a gas and so on now what happens if you 1414 00:37:11,490 --> 00:37:11,500 gas and so on now what happens if you 1415 00:37:11,500 --> 00:37:12,750 gas and so on now what happens if you decrease the temperature entropy 1416 00:37:12,750 --> 00:37:12,760 decrease the temperature entropy 1417 00:37:12,760 --> 00:37:16,530 decrease the temperature entropy decreases why because the translational 1418 00:37:16,530 --> 00:37:16,540 decreases why because the translational 1419 00:37:16,540 --> 00:37:17,940 decreases why because the translational motion kinetic energy of the molecule 1420 00:37:17,940 --> 00:37:17,950 motion kinetic energy of the molecule 1421 00:37:17,950 --> 00:37:20,339 motion kinetic energy of the molecule decreases because the vibrational 1422 00:37:20,339 --> 00:37:20,349 decreases because the vibrational 1423 00:37:20,349 --> 00:37:22,680 decreases because the vibrational motions are decreases rotational 1424 00:37:22,680 --> 00:37:22,690 motions are decreases rotational 1425 00:37:22,690 --> 00:37:25,140 motions are decreases rotational everything is decreasing as ATP so how 1426 00:37:25,140 --> 00:37:25,150 everything is decreasing as ATP so how 1427 00:37:25,150 --> 00:37:29,339 everything is decreasing as ATP so how far we can go down we can go to zero 1428 00:37:29,339 --> 00:37:29,349 far we can go down we can go to zero 1429 00:37:29,349 --> 00:37:31,829 far we can go down we can go to zero Kelvin right now when you go to the zero 1430 00:37:31,829 --> 00:37:31,839 Kelvin right now when you go to the zero 1431 00:37:31,839 --> 00:37:38,059 Kelvin right now when you go to the zero Kelvin then every motions will stop 1432 00:37:38,059 --> 00:37:38,069 Kelvin then every motions will stop 1433 00:37:38,069 --> 00:37:42,000 Kelvin then every motions will stop right those motions will turn off no 1434 00:37:42,000 --> 00:37:42,010 right those motions will turn off no 1435 00:37:42,010 --> 00:37:44,940 right those motions will turn off no translational no vibration no rotations 1436 00:37:44,940 --> 00:37:44,950 translational no vibration no rotations 1437 00:37:44,950 --> 00:37:51,120 translational no vibration no rotations now if you also have a solid with a 1438 00:37:51,120 --> 00:37:51,130 now if you also have a solid with a 1439 00:37:51,130 --> 00:37:55,109 now if you also have a solid with a perfect structure pure compound solid 1440 00:37:55,109 --> 00:37:55,119 perfect structure pure compound solid 1441 00:37:55,119 --> 00:37:58,500 perfect structure pure compound solid crystalline structure right no 1442 00:37:58,500 --> 00:37:58,510 crystalline structure right no 1443 00:37:58,510 --> 00:38:03,990 crystalline structure right no impurities that point at zero Kelvin no 1444 00:38:03,990 --> 00:38:04,000 impurities that point at zero Kelvin no 1445 00:38:04,000 --> 00:38:06,950 impurities that point at zero Kelvin no motions perfect order 1446 00:38:06,950 --> 00:38:06,960 motions perfect order 1447 00:38:06,960 --> 00:38:12,380 motions perfect order means the entropy is zero right so this 1448 00:38:12,380 --> 00:38:12,390 means the entropy is zero right so this 1449 00:38:12,390 --> 00:38:14,960 means the entropy is zero right so this is the third law of thermodynamics 1450 00:38:14,960 --> 00:38:14,970 is the third law of thermodynamics 1451 00:38:14,970 --> 00:38:18,650 is the third law of thermodynamics thermodynamics simply says that at zero 1452 00:38:18,650 --> 00:38:18,660 thermodynamics simply says that at zero 1453 00:38:18,660 --> 00:38:23,540 thermodynamics simply says that at zero Kelvin for pure crystalline perfect 1454 00:38:23,540 --> 00:38:23,550 Kelvin for pure crystalline perfect 1455 00:38:23,550 --> 00:38:26,990 Kelvin for pure crystalline perfect crystalline substances the entropy is 1456 00:38:26,990 --> 00:38:27,000 crystalline substances the entropy is 1457 00:38:27,000 --> 00:38:30,920 crystalline substances the entropy is zero entropy is zero now then if you 1458 00:38:30,920 --> 00:38:30,930 zero entropy is zero now then if you 1459 00:38:30,930 --> 00:38:33,680 zero entropy is zero now then if you increase the temperature the entropy 1460 00:38:33,680 --> 00:38:33,690 increase the temperature the entropy 1461 00:38:33,690 --> 00:38:35,840 increase the temperature the entropy will increase can we calculate that yes 1462 00:38:35,840 --> 00:38:35,850 will increase can we calculate that yes 1463 00:38:35,850 --> 00:38:38,120 will increase can we calculate that yes we can calculate that if you simply know 1464 00:38:38,120 --> 00:38:38,130 we can calculate that if you simply know 1465 00:38:38,130 --> 00:38:40,730 we can calculate that if you simply know the heat capacity of the substance at 1466 00:38:40,730 --> 00:38:40,740 the heat capacity of the substance at 1467 00:38:40,740 --> 00:38:43,640 the heat capacity of the substance at different temperatures and we know at 1468 00:38:43,640 --> 00:38:43,650 different temperatures and we know at 1469 00:38:43,650 --> 00:38:48,590 different temperatures and we know at melting and boiling it simply Delta H 1470 00:38:48,590 --> 00:38:48,600 melting and boiling it simply Delta H 1471 00:38:48,600 --> 00:38:51,170 melting and boiling it simply Delta H fusion and Delta H vaporization we can 1472 00:38:51,170 --> 00:38:51,180 fusion and Delta H vaporization we can 1473 00:38:51,180 --> 00:38:55,250 fusion and Delta H vaporization we can calculate the entropy of a substance or 1474 00:38:55,250 --> 00:38:55,260 calculate the entropy of a substance or 1475 00:38:55,260 --> 00:38:57,170 calculate the entropy of a substance or a compound whatever 1476 00:38:57,170 --> 00:38:57,180 a compound whatever 1477 00:38:57,180 --> 00:39:01,670 a compound whatever in fact at a temperature somewhere at a 1478 00:39:01,670 --> 00:39:01,680 in fact at a temperature somewhere at a 1479 00:39:01,680 --> 00:39:05,480 in fact at a temperature somewhere at a temperature for example suppose that we 1480 00:39:05,480 --> 00:39:05,490 temperature for example suppose that we 1481 00:39:05,490 --> 00:39:08,450 temperature for example suppose that we simply have hydrogen gas right and the 1482 00:39:08,450 --> 00:39:08,460 simply have hydrogen gas right and the 1483 00:39:08,460 --> 00:39:11,180 simply have hydrogen gas right and the hydrogen gas let's say at 25 degree 1484 00:39:11,180 --> 00:39:11,190 hydrogen gas let's say at 25 degree 1485 00:39:11,190 --> 00:39:13,730 hydrogen gas let's say at 25 degree centigrade if this is hydrogen gas it's 1486 00:39:13,730 --> 00:39:13,740 centigrade if this is hydrogen gas it's 1487 00:39:13,740 --> 00:39:15,740 centigrade if this is hydrogen gas it's not actually but it will be equal to 1488 00:39:15,740 --> 00:39:15,750 not actually but it will be equal to 1489 00:39:15,750 --> 00:39:18,650 not actually but it will be equal to this value here right not now aver these 1490 00:39:18,650 --> 00:39:18,660 this value here right not now aver these 1491 00:39:18,660 --> 00:39:21,350 this value here right not now aver these will be calculated now you see again as 1492 00:39:21,350 --> 00:39:21,360 will be calculated now you see again as 1493 00:39:21,360 --> 00:39:23,540 will be calculated now you see again as the temperature increases this is the 1494 00:39:23,540 --> 00:39:23,550 the temperature increases this is the 1495 00:39:23,550 --> 00:39:27,140 the temperature increases this is the solids at 0 Kelvin right and temperature 1496 00:39:27,140 --> 00:39:27,150 solids at 0 Kelvin right and temperature 1497 00:39:27,150 --> 00:39:28,900 solids at 0 Kelvin right and temperature increases the entropy will increase 1498 00:39:28,900 --> 00:39:28,910 increases the entropy will increase 1499 00:39:28,910 --> 00:39:32,530 increases the entropy will increase increase increase due to what do to the 1500 00:39:32,530 --> 00:39:32,540 increase increase due to what do to the 1501 00:39:32,540 --> 00:39:35,710 increase increase due to what do to the vibrational motions rotational motions 1502 00:39:35,710 --> 00:39:35,720 vibrational motions rotational motions 1503 00:39:35,720 --> 00:39:39,560 vibrational motions rotational motions actually and translational actually not 1504 00:39:39,560 --> 00:39:39,570 actually and translational actually not 1505 00:39:39,570 --> 00:39:41,000 actually and translational actually not in the solid but v2 the vibrational 1506 00:39:41,000 --> 00:39:41,010 in the solid but v2 the vibrational 1507 00:39:41,010 --> 00:39:43,880 in the solid but v2 the vibrational action now when you get to the mountain 1508 00:39:43,880 --> 00:39:43,890 action now when you get to the mountain 1509 00:39:43,890 --> 00:39:45,380 action now when you get to the mountain point here right 1510 00:39:45,380 --> 00:39:45,390 point here right 1511 00:39:45,390 --> 00:39:48,290 point here right without the temperature increase we give 1512 00:39:48,290 --> 00:39:48,300 without the temperature increase we give 1513 00:39:48,300 --> 00:39:51,290 without the temperature increase we give heat to the system and then melt it up 1514 00:39:51,290 --> 00:39:51,300 heat to the system and then melt it up 1515 00:39:51,300 --> 00:39:54,470 heat to the system and then melt it up to here so at this point here all of the 1516 00:39:54,470 --> 00:39:54,480 to here so at this point here all of the 1517 00:39:54,480 --> 00:39:58,250 to here so at this point here all of the solid that pure crystal there is liquid 1518 00:39:58,250 --> 00:39:58,260 solid that pure crystal there is liquid 1519 00:39:58,260 --> 00:40:01,850 solid that pure crystal there is liquid right so the entropy is that much there 1520 00:40:01,850 --> 00:40:01,860 right so the entropy is that much there 1521 00:40:01,860 --> 00:40:04,430 right so the entropy is that much there and then we increase the temperature of 1522 00:40:04,430 --> 00:40:04,440 and then we increase the temperature of 1523 00:40:04,440 --> 00:40:07,180 and then we increase the temperature of the liquids and then here it is the 1524 00:40:07,180 --> 00:40:07,190 the liquids and then here it is the 1525 00:40:07,190 --> 00:40:10,000 the liquids and then here it is the boiling point here right it all 1526 00:40:10,000 --> 00:40:10,010 boiling point here right it all 1527 00:40:10,010 --> 00:40:13,310 boiling point here right it all vaporizes right temperature the same 1528 00:40:13,310 --> 00:40:13,320 vaporizes right temperature the same 1529 00:40:13,320 --> 00:40:15,950 vaporizes right temperature the same temperature and the entropy increases 1530 00:40:15,950 --> 00:40:15,960 temperature and the entropy increases 1531 00:40:15,960 --> 00:40:18,260 temperature and the entropy increases and then we go here and so on what does 1532 00:40:18,260 --> 00:40:18,270 and then we go here and so on what does 1533 00:40:18,270 --> 00:40:20,420 and then we go here and so on what does that mean that simply means that if I 1534 00:40:20,420 --> 00:40:20,430 that mean that simply means that if I 1535 00:40:20,430 --> 00:40:21,040 that mean that simply means that if I know that 1536 00:40:21,040 --> 00:40:21,050 know that 1537 00:40:21,050 --> 00:40:24,850 know that data enough data and we do have the data 1538 00:40:24,850 --> 00:40:24,860 data enough data and we do have the data 1539 00:40:24,860 --> 00:40:30,570 data enough data and we do have the data I can calculate the entropy of any 1540 00:40:30,570 --> 00:40:30,580 I can calculate the entropy of any 1541 00:40:30,580 --> 00:40:34,930 I can calculate the entropy of any system at certain temperatures right at 1542 00:40:34,930 --> 00:40:34,940 system at certain temperatures right at 1543 00:40:34,940 --> 00:40:38,170 system at certain temperatures right at certain temperatures and that entropy is 1544 00:40:38,170 --> 00:40:38,180 certain temperatures and that entropy is 1545 00:40:38,180 --> 00:40:42,100 certain temperatures and that entropy is simply called the standard entropy of 1546 00:40:42,100 --> 00:40:42,110 simply called the standard entropy of 1547 00:40:42,110 --> 00:40:45,100 simply called the standard entropy of the system again standard entropy of the 1548 00:40:45,100 --> 00:40:45,110 the system again standard entropy of the 1549 00:40:45,110 --> 00:40:48,100 the system again standard entropy of the system and here are the standard entropy 1550 00:40:48,100 --> 00:40:48,110 system and here are the standard entropy 1551 00:40:48,110 --> 00:40:51,700 system and here are the standard entropy of the hydrogen nitrogen oxygen gas 1552 00:40:51,700 --> 00:40:51,710 of the hydrogen nitrogen oxygen gas 1553 00:40:51,710 --> 00:40:54,670 of the hydrogen nitrogen oxygen gas these are the things again sodium and so 1554 00:40:54,670 --> 00:40:54,680 these are the things again sodium and so 1555 00:40:54,680 --> 00:40:56,830 these are the things again sodium and so on you see again the hydrogen gas this 1556 00:40:56,830 --> 00:40:56,840 on you see again the hydrogen gas this 1557 00:40:56,840 --> 00:41:00,280 on you see again the hydrogen gas this is again joules per mole per Kelvin this 1558 00:41:00,280 --> 00:41:00,290 is again joules per mole per Kelvin this 1559 00:41:00,290 --> 00:41:03,240 is again joules per mole per Kelvin this means for one mole of hydrogen again at 1560 00:41:03,240 --> 00:41:03,250 means for one mole of hydrogen again at 1561 00:41:03,250 --> 00:41:06,730 means for one mole of hydrogen again at 25 degrees Kelvin no 25 degree 1562 00:41:06,730 --> 00:41:06,740 25 degrees Kelvin no 25 degree 1563 00:41:06,740 --> 00:41:10,810 25 degrees Kelvin no 25 degree centigrade 298 Kelvin is equals to 130 1564 00:41:10,810 --> 00:41:10,820 centigrade 298 Kelvin is equals to 130 1565 00:41:10,820 --> 00:41:16,660 centigrade 298 Kelvin is equals to 130 point 6 joules per Kelvin that is the 1566 00:41:16,660 --> 00:41:16,670 point 6 joules per Kelvin that is the 1567 00:41:16,670 --> 00:41:20,860 point 6 joules per Kelvin that is the entropy of one mole of hydrogen now when 1568 00:41:20,860 --> 00:41:20,870 entropy of one mole of hydrogen now when 1569 00:41:20,870 --> 00:41:22,720 entropy of one mole of hydrogen now when you go to the nitrogen again you see 1570 00:41:22,720 --> 00:41:22,730 you go to the nitrogen again you see 1571 00:41:22,730 --> 00:41:25,990 you go to the nitrogen again you see it's little greater right 191 because we 1572 00:41:25,990 --> 00:41:26,000 it's little greater right 191 because we 1573 00:41:26,000 --> 00:41:30,220 it's little greater right 191 because we are dealing with larger atoms nitrogen 1574 00:41:30,220 --> 00:41:30,230 are dealing with larger atoms nitrogen 1575 00:41:30,230 --> 00:41:32,830 are dealing with larger atoms nitrogen is larger than hydrogen and the oxygen 1576 00:41:32,830 --> 00:41:32,840 is larger than hydrogen and the oxygen 1577 00:41:32,840 --> 00:41:37,810 is larger than hydrogen and the oxygen and then goes to water and ammonia and 1578 00:41:37,810 --> 00:41:37,820 and then goes to water and ammonia and 1579 00:41:37,820 --> 00:41:40,740 and then goes to water and ammonia and so on so these are the standard 1580 00:41:40,740 --> 00:41:40,750 so on so these are the standard 1581 00:41:40,750 --> 00:41:46,120 so on so these are the standard entropies of the substances at 298 1582 00:41:46,120 --> 00:41:46,130 entropies of the substances at 298 1583 00:41:46,130 --> 00:41:49,090 entropies of the substances at 298 Kelvin or 25 Kelvin 1584 00:41:49,090 --> 00:41:49,100 Kelvin or 25 Kelvin 1585 00:41:49,100 --> 00:41:51,130 Kelvin or 25 Kelvin now these are again called standard 1586 00:41:51,130 --> 00:41:51,140 now these are again called standard 1587 00:41:51,140 --> 00:41:55,030 now these are again called standard molar enthalpy for gases are generally 1588 00:41:55,030 --> 00:41:55,040 molar enthalpy for gases are generally 1589 00:41:55,040 --> 00:41:57,720 molar enthalpy for gases are generally greater than the liquids and solids 1590 00:41:57,720 --> 00:41:57,730 greater than the liquids and solids 1591 00:41:57,730 --> 00:42:02,200 greater than the liquids and solids enthalpy yes now says be careful about 1592 00:42:02,200 --> 00:42:02,210 enthalpy yes now says be careful about 1593 00:42:02,210 --> 00:42:04,090 enthalpy yes now says be careful about the size here and the standard entropy 1594 00:42:04,090 --> 00:42:04,100 the size here and the standard entropy 1595 00:42:04,100 --> 00:42:06,640 the size here and the standard entropy increases with molar mass again that 1596 00:42:06,640 --> 00:42:06,650 increases with molar mass again that 1597 00:42:06,650 --> 00:42:10,330 increases with molar mass again that means the bigger the molecule the larger 1598 00:42:10,330 --> 00:42:10,340 means the bigger the molecule the larger 1599 00:42:10,340 --> 00:42:13,000 means the bigger the molecule the larger it is standard entropy but not that much 1600 00:42:13,000 --> 00:42:13,010 it is standard entropy but not that much 1601 00:42:13,010 --> 00:42:14,980 it is standard entropy but not that much actually you see again it changes from 1602 00:42:14,980 --> 00:42:14,990 actually you see again it changes from 1603 00:42:14,990 --> 00:42:17,890 actually you see again it changes from what hundred and thirty or let's say 1604 00:42:17,890 --> 00:42:17,900 what hundred and thirty or let's say 1605 00:42:17,900 --> 00:42:19,720 what hundred and thirty or let's say what is the lowest one here the lowest 1606 00:42:19,720 --> 00:42:19,730 what is the lowest one here the lowest 1607 00:42:19,730 --> 00:42:22,690 what is the lowest one here the lowest one is about what 72 even this is the 1608 00:42:22,690 --> 00:42:22,700 one is about what 72 even this is the 1609 00:42:22,700 --> 00:42:26,590 one is about what 72 even this is the solid and the largest one is probably 1610 00:42:26,590 --> 00:42:26,600 solid and the largest one is probably 1611 00:42:26,600 --> 00:42:31,900 solid and the largest one is probably about what 192 or this one 205 so that's 1612 00:42:31,900 --> 00:42:31,910 about what 192 or this one 205 so that's 1613 00:42:31,910 --> 00:42:34,660 about what 192 or this one 205 so that's not that much actually 1614 00:42:34,660 --> 00:42:34,670 not that much actually 1615 00:42:34,670 --> 00:42:37,990 not that much actually I mean not like 10 or 20 times like less 1616 00:42:37,990 --> 00:42:38,000 I mean not like 10 or 20 times like less 1617 00:42:38,000 --> 00:42:40,450 I mean not like 10 or 20 times like less than two times but these are the 1618 00:42:40,450 --> 00:42:40,460 than two times but these are the 1619 00:42:40,460 --> 00:42:44,019 than two times but these are the standard entropies what are they're good 1620 00:42:44,019 --> 00:42:44,029 standard entropies what are they're good 1621 00:42:44,029 --> 00:42:50,220 standard entropies what are they're good for they're good for calculating 1622 00:42:50,220 --> 00:42:50,230 for they're good for calculating 1623 00:42:50,230 --> 00:42:53,200 for they're good for calculating standard entropy change for a chemical 1624 00:42:53,200 --> 00:42:53,210 standard entropy change for a chemical 1625 00:42:53,210 --> 00:42:56,170 standard entropy change for a chemical reaction right chemical reaction now 1626 00:42:56,170 --> 00:42:56,180 reaction right chemical reaction now 1627 00:42:56,180 --> 00:43:01,059 reaction right chemical reaction now remember again to calculate the enthalpy 1628 00:43:01,059 --> 00:43:01,069 remember again to calculate the enthalpy 1629 00:43:01,069 --> 00:43:04,740 remember again to calculate the enthalpy change of a chemical reaction we use the 1630 00:43:04,740 --> 00:43:04,750 change of a chemical reaction we use the 1631 00:43:04,750 --> 00:43:09,730 change of a chemical reaction we use the standard enthalpies of formations right 1632 00:43:09,730 --> 00:43:09,740 standard enthalpies of formations right 1633 00:43:09,740 --> 00:43:11,829 standard enthalpies of formations right standard enthalpies of formation now 1634 00:43:11,829 --> 00:43:11,839 standard enthalpies of formation now 1635 00:43:11,839 --> 00:43:13,569 standard enthalpies of formation now remember in those cases the in turn end 1636 00:43:13,569 --> 00:43:13,579 remember in those cases the in turn end 1637 00:43:13,579 --> 00:43:17,250 remember in those cases the in turn end up your formation was actually the 1638 00:43:17,250 --> 00:43:17,260 up your formation was actually the 1639 00:43:17,260 --> 00:43:22,680 up your formation was actually the enthalpy change of a reaction in which a 1640 00:43:22,680 --> 00:43:22,690 enthalpy change of a reaction in which a 1641 00:43:22,690 --> 00:43:26,319 enthalpy change of a reaction in which a substance is formed from its pure 1642 00:43:26,319 --> 00:43:26,329 substance is formed from its pure 1643 00:43:26,329 --> 00:43:28,720 substance is formed from its pure elements understand standard state 1644 00:43:28,720 --> 00:43:28,730 elements understand standard state 1645 00:43:28,730 --> 00:43:32,289 elements understand standard state conditions right so actually the 1646 00:43:32,289 --> 00:43:32,299 conditions right so actually the 1647 00:43:32,299 --> 00:43:36,069 conditions right so actually the enthalpy of formation corresponds to the 1648 00:43:36,069 --> 00:43:36,079 enthalpy of formation corresponds to the 1649 00:43:36,079 --> 00:43:39,789 enthalpy of formation corresponds to the formations of that substance from its 1650 00:43:39,789 --> 00:43:39,799 formations of that substance from its 1651 00:43:39,799 --> 00:43:42,759 formations of that substance from its pure elements under standard conditions 1652 00:43:42,759 --> 00:43:42,769 pure elements under standard conditions 1653 00:43:42,769 --> 00:43:46,539 pure elements under standard conditions and therefore the standard enthalpy of 1654 00:43:46,539 --> 00:43:46,549 and therefore the standard enthalpy of 1655 00:43:46,549 --> 00:43:49,900 and therefore the standard enthalpy of formation for pure elements at their 1656 00:43:49,900 --> 00:43:49,910 formation for pure elements at their 1657 00:43:49,910 --> 00:43:53,999 formation for pure elements at their standard states is assumed to be what 1658 00:43:53,999 --> 00:43:54,009 1659 00:43:54,009 --> 00:43:56,349 standard enthalpy of formation for pure 1660 00:43:56,349 --> 00:43:56,359 standard enthalpy of formation for pure 1661 00:43:56,359 --> 00:43:59,890 standard enthalpy of formation for pure substance at standard state zero how 1662 00:43:59,890 --> 00:43:59,900 substance at standard state zero how 1663 00:43:59,900 --> 00:44:03,999 substance at standard state zero how about here is the standard entropies are 1664 00:44:03,999 --> 00:44:04,009 about here is the standard entropies are 1665 00:44:04,009 --> 00:44:05,009 about here is the standard entropies are zero 1666 00:44:05,009 --> 00:44:05,019 zero 1667 00:44:05,019 --> 00:44:09,940 zero no it is not for pure elements actually 1668 00:44:09,940 --> 00:44:09,950 no it is not for pure elements actually 1669 00:44:09,950 --> 00:44:11,640 no it is not for pure elements actually as you see over here for example 1670 00:44:11,640 --> 00:44:11,650 as you see over here for example 1671 00:44:11,650 --> 00:44:16,740 as you see over here for example standard entropy of hydrogen is 130 1672 00:44:16,740 --> 00:44:16,750 standard entropy of hydrogen is 130 1673 00:44:16,750 --> 00:44:20,349 standard entropy of hydrogen is 130 nitrogen oxygen all of these standard 1674 00:44:20,349 --> 00:44:20,359 nitrogen oxygen all of these standard 1675 00:44:20,359 --> 00:44:22,450 nitrogen oxygen all of these standard enthalpies of formations for all these 1676 00:44:22,450 --> 00:44:22,460 enthalpies of formations for all these 1677 00:44:22,460 --> 00:44:26,440 enthalpies of formations for all these are zero right but for the standard 1678 00:44:26,440 --> 00:44:26,450 are zero right but for the standard 1679 00:44:26,450 --> 00:44:31,269 are zero right but for the standard entropy they are not zero now let's look 1680 00:44:31,269 --> 00:44:31,279 entropy they are not zero now let's look 1681 00:44:31,279 --> 00:44:34,539 entropy they are not zero now let's look at here again now there is an error here 1682 00:44:34,539 --> 00:44:34,549 at here again now there is an error here 1683 00:44:34,549 --> 00:44:41,339 at here again now there is an error here let's see can you find that error now 1684 00:44:41,339 --> 00:44:41,349 let's see can you find that error now 1685 00:44:41,349 --> 00:44:44,499 let's see can you find that error now here how we indicate the standard 1686 00:44:44,499 --> 00:44:44,509 here how we indicate the standard 1687 00:44:44,509 --> 00:44:48,540 here how we indicate the standard entropy right 1688 00:44:48,540 --> 00:44:48,550 entropy right 1689 00:44:48,550 --> 00:44:55,780 entropy right only s to the not right zero here now 1690 00:44:55,780 --> 00:44:55,790 only s to the not right zero here now 1691 00:44:55,790 --> 00:45:03,700 only s to the not right zero here now here that will not be there right it 1692 00:45:03,700 --> 00:45:03,710 here that will not be there right it 1693 00:45:03,710 --> 00:45:08,050 here that will not be there right it will not be Delta this is also will not 1694 00:45:08,050 --> 00:45:08,060 will not be Delta this is also will not 1695 00:45:08,060 --> 00:45:11,380 will not be Delta this is also will not be Delta V R but this is Delta the 1696 00:45:11,380 --> 00:45:11,390 be Delta V R but this is Delta the 1697 00:45:11,390 --> 00:45:14,190 be Delta V R but this is Delta the entropy change in a chemical reactions 1698 00:45:14,190 --> 00:45:14,200 entropy change in a chemical reactions 1699 00:45:14,200 --> 00:45:19,330 entropy change in a chemical reactions right some of the standard entropies of 1700 00:45:19,330 --> 00:45:19,340 right some of the standard entropies of 1701 00:45:19,340 --> 00:45:22,870 right some of the standard entropies of the product that Delta s zero does not 1702 00:45:22,870 --> 00:45:22,880 the product that Delta s zero does not 1703 00:45:22,880 --> 00:45:25,000 the product that Delta s zero does not stand for standard entropy because here 1704 00:45:25,000 --> 00:45:25,010 stand for standard entropy because here 1705 00:45:25,010 --> 00:45:27,030 stand for standard entropy because here here is the exact I mean look at this 1706 00:45:27,030 --> 00:45:27,040 here is the exact I mean look at this 1707 00:45:27,040 --> 00:45:29,680 here is the exact I mean look at this this table here this is the correct form 1708 00:45:29,680 --> 00:45:29,690 this table here this is the correct form 1709 00:45:29,690 --> 00:45:32,190 this table here this is the correct form of standard entropy as to the zero and 1710 00:45:32,190 --> 00:45:32,200 of standard entropy as to the zero and 1711 00:45:32,200 --> 00:45:35,770 of standard entropy as to the zero and but again remember that that's not going 1712 00:45:35,770 --> 00:45:35,780 but again remember that that's not going 1713 00:45:35,780 --> 00:45:38,200 but again remember that that's not going to be there that Delta and that Delta - 1714 00:45:38,200 --> 00:45:38,210 to be there that Delta and that Delta - 1715 00:45:38,210 --> 00:45:41,530 to be there that Delta and that Delta - but it once you know the standard 1716 00:45:41,530 --> 00:45:41,540 but it once you know the standard 1717 00:45:41,540 --> 00:45:43,330 but it once you know the standard entropies of the reactants and the 1718 00:45:43,330 --> 00:45:43,340 entropies of the reactants and the 1719 00:45:43,340 --> 00:45:45,850 entropies of the reactants and the products you can calculate the entropy 1720 00:45:45,850 --> 00:45:45,860 products you can calculate the entropy 1721 00:45:45,860 --> 00:45:48,610 products you can calculate the entropy change standard entropy change for the 1722 00:45:48,610 --> 00:45:48,620 change standard entropy change for the 1723 00:45:48,620 --> 00:45:50,980 change standard entropy change for the chemical reaction using this formula 1724 00:45:50,980 --> 00:45:50,990 chemical reaction using this formula 1725 00:45:50,990 --> 00:45:54,160 chemical reaction using this formula right using this formula well now again 1726 00:45:54,160 --> 00:45:54,170 right using this formula well now again 1727 00:45:54,170 --> 00:45:56,890 right using this formula well now again N and M are the coefficients in the 1728 00:45:56,890 --> 00:45:56,900 N and M are the coefficients in the 1729 00:45:56,900 --> 00:45:59,020 N and M are the coefficients in the balance chemical equations coefficients 1730 00:45:59,020 --> 00:45:59,030 balance chemical equations coefficients 1731 00:45:59,030 --> 00:46:04,260 balance chemical equations coefficients in the balance chemical equations now 1732 00:46:04,260 --> 00:46:04,270 in the balance chemical equations now 1733 00:46:04,270 --> 00:46:07,000 in the balance chemical equations now how about the entropy changes in the 1734 00:46:07,000 --> 00:46:07,010 how about the entropy changes in the 1735 00:46:07,010 --> 00:46:10,810 how about the entropy changes in the surroundings yes we can simply calculate 1736 00:46:10,810 --> 00:46:10,820 surroundings yes we can simply calculate 1737 00:46:10,820 --> 00:46:12,610 surroundings yes we can simply calculate the entropy change of the surrounding 1738 00:46:12,610 --> 00:46:12,620 the entropy change of the surrounding 1739 00:46:12,620 --> 00:46:15,520 the entropy change of the surrounding heat that flows into or out of the 1740 00:46:15,520 --> 00:46:15,530 heat that flows into or out of the 1741 00:46:15,530 --> 00:46:17,290 heat that flows into or out of the system changes the entropy of the 1742 00:46:17,290 --> 00:46:17,300 system changes the entropy of the 1743 00:46:17,300 --> 00:46:21,370 system changes the entropy of the Saranda right now for an isothermal 1744 00:46:21,370 --> 00:46:21,380 Saranda right now for an isothermal 1745 00:46:21,380 --> 00:46:26,350 Saranda right now for an isothermal process isothermal means constant 1746 00:46:26,350 --> 00:46:26,360 process isothermal means constant 1747 00:46:26,360 --> 00:46:28,360 process isothermal means constant temperature process temperature process 1748 00:46:28,360 --> 00:46:28,370 temperature process temperature process 1749 00:46:28,370 --> 00:46:31,360 temperature process temperature process the Delta s surrounding would be equal 1750 00:46:31,360 --> 00:46:31,370 the Delta s surrounding would be equal 1751 00:46:31,370 --> 00:46:35,770 the Delta s surrounding would be equal to minus Q system divided by that 1752 00:46:35,770 --> 00:46:35,780 to minus Q system divided by that 1753 00:46:35,780 --> 00:46:44,050 to minus Q system divided by that temperature now what does that means now 1754 00:46:44,050 --> 00:46:44,060 temperature now what does that means now 1755 00:46:44,060 --> 00:46:49,780 temperature now what does that means now suppose that the two for the system is 1756 00:46:49,780 --> 00:46:49,790 suppose that the two for the system is 1757 00:46:49,790 --> 00:46:56,280 suppose that the two for the system is negative right what is negative means 1758 00:46:56,280 --> 00:46:56,290 negative right what is negative means 1759 00:46:56,290 --> 00:46:58,030 negative right what is negative means exothermic what does that mean that 1760 00:46:58,030 --> 00:46:58,040 exothermic what does that mean that 1761 00:46:58,040 --> 00:47:00,660 exothermic what does that mean that means the system releases heat 1762 00:47:00,660 --> 00:47:00,670 means the system releases heat 1763 00:47:00,670 --> 00:47:03,720 means the system releases heat to diss around it right so in that case 1764 00:47:03,720 --> 00:47:03,730 to diss around it right so in that case 1765 00:47:03,730 --> 00:47:06,680 to diss around it right so in that case if Q is negative another negative here 1766 00:47:06,680 --> 00:47:06,690 if Q is negative another negative here 1767 00:47:06,690 --> 00:47:09,480 if Q is negative another negative here divided by T Delta s Tirana will be 1768 00:47:09,480 --> 00:47:09,490 divided by T Delta s Tirana will be 1769 00:47:09,490 --> 00:47:12,029 divided by T Delta s Tirana will be positive very clear actually when the 1770 00:47:12,029 --> 00:47:12,039 positive very clear actually when the 1771 00:47:12,039 --> 00:47:14,339 positive very clear actually when the heat is given to the surrounding the 1772 00:47:14,339 --> 00:47:14,349 heat is given to the surrounding the 1773 00:47:14,349 --> 00:47:16,109 heat is given to the surrounding the entropy of the surrounding increases 1774 00:47:16,109 --> 00:47:16,119 entropy of the surrounding increases 1775 00:47:16,119 --> 00:47:20,549 entropy of the surrounding increases right that's positive but if we see the 1776 00:47:20,549 --> 00:47:20,559 right that's positive but if we see the 1777 00:47:20,559 --> 00:47:23,609 right that's positive but if we see the the system observes heat from the 1778 00:47:23,609 --> 00:47:23,619 the system observes heat from the 1779 00:47:23,619 --> 00:47:27,720 the system observes heat from the surrounding then the heat content of the 1780 00:47:27,720 --> 00:47:27,730 surrounding then the heat content of the 1781 00:47:27,730 --> 00:47:29,640 surrounding then the heat content of the surrounding will decrease and that 1782 00:47:29,640 --> 00:47:29,650 surrounding will decrease and that 1783 00:47:29,650 --> 00:47:31,500 surrounding will decrease and that decrease means that entropy of the 1784 00:47:31,500 --> 00:47:31,510 decrease means that entropy of the 1785 00:47:31,510 --> 00:47:33,630 decrease means that entropy of the surrounding result also decrease so that 1786 00:47:33,630 --> 00:47:33,640 surrounding result also decrease so that 1787 00:47:33,640 --> 00:47:35,880 surrounding result also decrease so that sign is actually important now at 1788 00:47:35,880 --> 00:47:35,890 sign is actually important now at 1789 00:47:35,890 --> 00:47:38,160 sign is actually important now at constant pressure Q system is simply 1790 00:47:38,160 --> 00:47:38,170 constant pressure Q system is simply 1791 00:47:38,170 --> 00:47:42,720 constant pressure Q system is simply equals to Delta H for the system again a 1792 00:47:42,720 --> 00:47:42,730 equals to Delta H for the system again a 1793 00:47:42,730 --> 00:47:44,519 equals to Delta H for the system again a constant pressure remember under 1794 00:47:44,519 --> 00:47:44,529 constant pressure remember under 1795 00:47:44,529 --> 00:47:47,160 constant pressure remember under constant pressure Q system is equal to 1796 00:47:47,160 --> 00:47:47,170 constant pressure Q system is equal to 1797 00:47:47,170 --> 00:47:49,880 constant pressure Q system is equal to the enthalpy change Delta H so Delta s 1798 00:47:49,880 --> 00:47:49,890 the enthalpy change Delta H so Delta s 1799 00:47:49,890 --> 00:47:53,009 the enthalpy change Delta H so Delta s surrounding would be equal to minus 1800 00:47:53,009 --> 00:47:53,019 surrounding would be equal to minus 1801 00:47:53,019 --> 00:47:55,140 surrounding would be equal to minus Delta H system just that replaced by 1802 00:47:55,140 --> 00:47:55,150 Delta H system just that replaced by 1803 00:47:55,150 --> 00:47:57,509 Delta H system just that replaced by Delta H actually divided by T at 1804 00:47:57,509 --> 00:47:57,519 Delta H actually divided by T at 1805 00:47:57,519 --> 00:48:02,880 Delta H actually divided by T at constant pressure again now if I simply 1806 00:48:02,880 --> 00:48:02,890 constant pressure again now if I simply 1807 00:48:02,890 --> 00:48:09,630 constant pressure again now if I simply have the Delta s universe and it would 1808 00:48:09,630 --> 00:48:09,640 have the Delta s universe and it would 1809 00:48:09,640 --> 00:48:12,480 have the Delta s universe and it would be equal to Delta s system plus Delta s 1810 00:48:12,480 --> 00:48:12,490 be equal to Delta s system plus Delta s 1811 00:48:12,490 --> 00:48:14,849 be equal to Delta s system plus Delta s surroundings for spontaneous process 1812 00:48:14,849 --> 00:48:14,859 surroundings for spontaneous process 1813 00:48:14,859 --> 00:48:16,620 surroundings for spontaneous process Delta s universe will be greater than 1814 00:48:16,620 --> 00:48:16,630 Delta s universe will be greater than 1815 00:48:16,630 --> 00:48:19,940 Delta s universe will be greater than zero this is a game the second law of 1816 00:48:19,940 --> 00:48:19,950 zero this is a game the second law of 1817 00:48:19,950 --> 00:48:22,170 zero this is a game the second law of thermodynamics for spontaneous process 1818 00:48:22,170 --> 00:48:22,180 thermodynamics for spontaneous process 1819 00:48:22,180 --> 00:48:24,749 thermodynamics for spontaneous process the Delta s universe will be greater 1820 00:48:24,749 --> 00:48:24,759 the Delta s universe will be greater 1821 00:48:24,759 --> 00:48:33,180 the Delta s universe will be greater than zero and total entropy and the 1822 00:48:33,180 --> 00:48:33,190 than zero and total entropy and the 1823 00:48:33,190 --> 00:48:35,819 than zero and total entropy and the spontaneity how the entropy and the 1824 00:48:35,819 --> 00:48:35,829 spontaneity how the entropy and the 1825 00:48:35,829 --> 00:48:38,849 spontaneity how the entropy and the spontaneity are related again Delta s 1826 00:48:38,849 --> 00:48:38,859 spontaneity are related again Delta s 1827 00:48:38,859 --> 00:48:41,849 spontaneity are related again Delta s universe is equal to Delta s system plus 1828 00:48:41,849 --> 00:48:41,859 universe is equal to Delta s system plus 1829 00:48:41,859 --> 00:48:45,420 universe is equal to Delta s system plus Delta s surroundings yes now when we 1830 00:48:45,420 --> 00:48:45,430 Delta s surroundings yes now when we 1831 00:48:45,430 --> 00:48:48,569 Delta s surroundings yes now when we substitute the Delta s surrounding with 1832 00:48:48,569 --> 00:48:48,579 substitute the Delta s surrounding with 1833 00:48:48,579 --> 00:48:50,490 substitute the Delta s surrounding with Delta s system divided by T which we 1834 00:48:50,490 --> 00:48:50,500 Delta s system divided by T which we 1835 00:48:50,500 --> 00:48:53,099 Delta s system divided by T which we have simply defined before and Delta s 1836 00:48:53,099 --> 00:48:53,109 have simply defined before and Delta s 1837 00:48:53,109 --> 00:48:55,009 have simply defined before and Delta s universe will be equal to Delta s system 1838 00:48:55,009 --> 00:48:55,019 universe will be equal to Delta s system 1839 00:48:55,019 --> 00:49:00,120 universe will be equal to Delta s system minus Delta H system and T all right now 1840 00:49:00,120 --> 00:49:00,130 minus Delta H system and T all right now 1841 00:49:00,130 --> 00:49:02,849 minus Delta H system and T all right now if I multiply both sides of this 1842 00:49:02,849 --> 00:49:02,859 if I multiply both sides of this 1843 00:49:02,859 --> 00:49:05,730 if I multiply both sides of this equation by minus T over here like this 1844 00:49:05,730 --> 00:49:05,740 equation by minus T over here like this 1845 00:49:05,740 --> 00:49:08,160 equation by minus T over here like this and I get simply minus T Delta s 1846 00:49:08,160 --> 00:49:08,170 and I get simply minus T Delta s 1847 00:49:08,170 --> 00:49:12,029 and I get simply minus T Delta s universe and minus T Delta s system and 1848 00:49:12,029 --> 00:49:12,039 universe and minus T Delta s system and 1849 00:49:12,039 --> 00:49:14,260 universe and minus T Delta s system and Delta H system that goes 1850 00:49:14,260 --> 00:49:14,270 Delta H system that goes 1851 00:49:14,270 --> 00:49:18,130 Delta H system that goes there now for the process to be 1852 00:49:18,130 --> 00:49:18,140 there now for the process to be 1853 00:49:18,140 --> 00:49:19,330 there now for the process to be spontaneous 1854 00:49:19,330 --> 00:49:19,340 spontaneous 1855 00:49:19,340 --> 00:49:22,330 spontaneous I guess rearrange that simply put that 1856 00:49:22,330 --> 00:49:22,340 I guess rearrange that simply put that 1857 00:49:22,340 --> 00:49:24,550 I guess rearrange that simply put that over here and this there and I have this 1858 00:49:24,550 --> 00:49:24,560 over here and this there and I have this 1859 00:49:24,560 --> 00:49:26,590 over here and this there and I have this equation here minus T Delta s universe 1860 00:49:26,590 --> 00:49:26,600 equation here minus T Delta s universe 1861 00:49:26,600 --> 00:49:29,650 equation here minus T Delta s universe equals to Delta H system minus T Delta s 1862 00:49:29,650 --> 00:49:29,660 equals to Delta H system minus T Delta s 1863 00:49:29,660 --> 00:49:35,070 equals to Delta H system minus T Delta s system now let's see what we have here 1864 00:49:35,070 --> 00:49:35,080 1865 00:49:35,080 --> 00:49:40,950 actually just go here for a spontaneous 1866 00:49:40,950 --> 00:49:40,960 actually just go here for a spontaneous 1867 00:49:40,960 --> 00:49:45,640 actually just go here for a spontaneous process since Delta s universe will be 1868 00:49:45,640 --> 00:49:45,650 process since Delta s universe will be 1869 00:49:45,650 --> 00:49:50,680 process since Delta s universe will be what spontaneous process Delta s 1870 00:49:50,680 --> 00:49:50,690 what spontaneous process Delta s 1871 00:49:50,690 --> 00:49:52,000 what spontaneous process Delta s universe will be what is the sign 1872 00:49:52,000 --> 00:49:52,010 universe will be what is the sign 1873 00:49:52,010 --> 00:49:54,850 universe will be what is the sign positive or negative positive it will be 1874 00:49:54,850 --> 00:49:54,860 positive or negative positive it will be 1875 00:49:54,860 --> 00:49:57,130 positive or negative positive it will be positive increasing so multiplying that 1876 00:49:57,130 --> 00:49:57,140 positive increasing so multiplying that 1877 00:49:57,140 --> 00:49:59,340 positive increasing so multiplying that minus T that means this will be negative 1878 00:49:59,340 --> 00:49:59,350 minus T that means this will be negative 1879 00:49:59,350 --> 00:50:01,960 minus T that means this will be negative right so what does that mean if this 1880 00:50:01,960 --> 00:50:01,970 right so what does that mean if this 1881 00:50:01,970 --> 00:50:06,790 right so what does that mean if this term is negative for a process minus T 1882 00:50:06,790 --> 00:50:06,800 term is negative for a process minus T 1883 00:50:06,800 --> 00:50:08,880 term is negative for a process minus T Delta as negative for the process that 1884 00:50:08,880 --> 00:50:08,890 Delta as negative for the process that 1885 00:50:08,890 --> 00:50:14,380 Delta as negative for the process that process is spontaneous right now how can 1886 00:50:14,380 --> 00:50:14,390 process is spontaneous right now how can 1887 00:50:14,390 --> 00:50:17,080 process is spontaneous right now how can I calculate that if I know that Delta s 1888 00:50:17,080 --> 00:50:17,090 I calculate that if I know that Delta s 1889 00:50:17,090 --> 00:50:19,450 I calculate that if I know that Delta s universe and minus T Delta s yes I can 1890 00:50:19,450 --> 00:50:19,460 universe and minus T Delta s yes I can 1891 00:50:19,460 --> 00:50:20,740 universe and minus T Delta s yes I can do that but it would be very difficult 1892 00:50:20,740 --> 00:50:20,750 do that but it would be very difficult 1893 00:50:20,750 --> 00:50:22,660 do that but it would be very difficult to calculate this Delta s universe here 1894 00:50:22,660 --> 00:50:22,670 to calculate this Delta s universe here 1895 00:50:22,670 --> 00:50:26,410 to calculate this Delta s universe here but if I know the Delta EIJ system that 1896 00:50:26,410 --> 00:50:26,420 but if I know the Delta EIJ system that 1897 00:50:26,420 --> 00:50:28,120 but if I know the Delta EIJ system that means the enthalpy change of the system 1898 00:50:28,120 --> 00:50:28,130 means the enthalpy change of the system 1899 00:50:28,130 --> 00:50:31,270 means the enthalpy change of the system and if I know the entropy change of the 1900 00:50:31,270 --> 00:50:31,280 and if I know the entropy change of the 1901 00:50:31,280 --> 00:50:33,580 and if I know the entropy change of the system remember I can calculate this 1902 00:50:33,580 --> 00:50:33,590 system remember I can calculate this 1903 00:50:33,590 --> 00:50:35,110 system remember I can calculate this entropy change from the standard entropy 1904 00:50:35,110 --> 00:50:35,120 entropy change from the standard entropy 1905 00:50:35,120 --> 00:50:38,050 entropy change from the standard entropy s if this is chemical reactions right so 1906 00:50:38,050 --> 00:50:38,060 s if this is chemical reactions right so 1907 00:50:38,060 --> 00:50:39,970 s if this is chemical reactions right so that means if I know the temperature by 1908 00:50:39,970 --> 00:50:39,980 that means if I know the temperature by 1909 00:50:39,980 --> 00:50:42,280 that means if I know the temperature by using these thermodynamic values I can 1910 00:50:42,280 --> 00:50:42,290 using these thermodynamic values I can 1911 00:50:42,290 --> 00:50:44,850 using these thermodynamic values I can find out whether the reaction is 1912 00:50:44,850 --> 00:50:44,860 find out whether the reaction is 1913 00:50:44,860 --> 00:50:48,340 find out whether the reaction is spontaneous or non-spontaneous or any 1914 00:50:48,340 --> 00:50:48,350 spontaneous or non-spontaneous or any 1915 00:50:48,350 --> 00:50:50,020 spontaneous or non-spontaneous or any process will be spontaneous or 1916 00:50:50,020 --> 00:50:50,030 process will be spontaneous or 1917 00:50:50,030 --> 00:50:53,650 process will be spontaneous or non-spontaneous so now this two is 1918 00:50:53,650 --> 00:50:53,660 non-spontaneous so now this two is 1919 00:50:53,660 --> 00:50:56,940 non-spontaneous so now this two is combined with a new function 1920 00:50:56,940 --> 00:50:56,950 combined with a new function 1921 00:50:56,950 --> 00:50:59,140 combined with a new function thermodynamic function which is called 1922 00:50:59,140 --> 00:50:59,150 thermodynamic function which is called 1923 00:50:59,150 --> 00:51:01,870 thermodynamic function which is called Gibbs free energy and it is designated 1924 00:51:01,870 --> 00:51:01,880 Gibbs free energy and it is designated 1925 00:51:01,880 --> 00:51:07,360 Gibbs free energy and it is designated by G capital G and simply the change in 1926 00:51:07,360 --> 00:51:07,370 by G capital G and simply the change in 1927 00:51:07,370 --> 00:51:10,720 by G capital G and simply the change in Gibbs free energy would be equals to 1928 00:51:10,720 --> 00:51:10,730 Gibbs free energy would be equals to 1929 00:51:10,730 --> 00:51:13,060 Gibbs free energy would be equals to this right here minus T Delta s universe 1930 00:51:13,060 --> 00:51:13,070 this right here minus T Delta s universe 1931 00:51:13,070 --> 00:51:16,030 this right here minus T Delta s universe and that's equal to Delta H T Delta s 1932 00:51:16,030 --> 00:51:16,040 and that's equal to Delta H T Delta s 1933 00:51:16,040 --> 00:51:21,940 and that's equal to Delta H T Delta s now all of these values are actually for 1934 00:51:21,940 --> 00:51:21,950 now all of these values are actually for 1935 00:51:21,950 --> 00:51:24,790 now all of these values are actually for the system Delta s system Delta H system 1936 00:51:24,790 --> 00:51:24,800 the system Delta s system Delta H system 1937 00:51:24,800 --> 00:51:26,800 the system Delta s system Delta H system and Delta G system all of those are now 1938 00:51:26,800 --> 00:51:26,810 and Delta G system all of those are now 1939 00:51:26,810 --> 00:51:28,090 and Delta G system all of those are now system let me 1940 00:51:28,090 --> 00:51:28,100 system let me 1941 00:51:28,100 --> 00:51:31,990 system let me if I know the enthalpy change of the 1942 00:51:31,990 --> 00:51:32,000 if I know the enthalpy change of the 1943 00:51:32,000 --> 00:51:34,240 if I know the enthalpy change of the system and the entropy change of the 1944 00:51:34,240 --> 00:51:34,250 system and the entropy change of the 1945 00:51:34,250 --> 00:51:37,000 system and the entropy change of the system at a given temperature I can find 1946 00:51:37,000 --> 00:51:37,010 system at a given temperature I can find 1947 00:51:37,010 --> 00:51:41,020 system at a given temperature I can find out the Delta G Y because by looking at 1948 00:51:41,020 --> 00:51:41,030 out the Delta G Y because by looking at 1949 00:51:41,030 --> 00:51:43,750 out the Delta G Y because by looking at the sign of the Delta G I can tell 1950 00:51:43,750 --> 00:51:43,760 the sign of the Delta G I can tell 1951 00:51:43,760 --> 00:51:46,450 the sign of the Delta G I can tell whether the reaction is spontaneous or 1952 00:51:46,450 --> 00:51:46,460 whether the reaction is spontaneous or 1953 00:51:46,460 --> 00:51:49,300 whether the reaction is spontaneous or the process is spontaneous or it is not 1954 00:51:49,300 --> 00:51:49,310 the process is spontaneous or it is not 1955 00:51:49,310 --> 00:51:51,760 the process is spontaneous or it is not spontaneous if now the G chips free 1956 00:51:51,760 --> 00:51:51,770 spontaneous if now the G chips free 1957 00:51:51,770 --> 00:51:53,410 spontaneous if now the G chips free energy change in the Gibbs free energy 1958 00:51:53,410 --> 00:51:53,420 energy change in the Gibbs free energy 1959 00:51:53,420 --> 00:51:56,430 energy change in the Gibbs free energy turns out to be negative means that the 1960 00:51:56,430 --> 00:51:56,440 turns out to be negative means that the 1961 00:51:56,440 --> 00:51:58,780 turns out to be negative means that the reaction or the process is spontaneous 1962 00:51:58,780 --> 00:51:58,790 reaction or the process is spontaneous 1963 00:51:58,790 --> 00:52:02,230 reaction or the process is spontaneous if it changes to be it comes out as 1964 00:52:02,230 --> 00:52:02,240 if it changes to be it comes out as 1965 00:52:02,240 --> 00:52:05,650 if it changes to be it comes out as positive means that that reaction or 1966 00:52:05,650 --> 00:52:05,660 positive means that that reaction or 1967 00:52:05,660 --> 00:52:07,960 positive means that that reaction or that process will not be spontaneous but 1968 00:52:07,960 --> 00:52:07,970 that process will not be spontaneous but 1969 00:52:07,970 --> 00:52:10,570 that process will not be spontaneous but the reverse will be spontaneous okay I 1970 00:52:10,570 --> 00:52:10,580 the reverse will be spontaneous okay I 1971 00:52:10,580 --> 00:52:13,230 the reverse will be spontaneous okay I guess we'll have to stop here and then 1972 00:52:13,230 --> 00:52:13,240 guess we'll have to stop here and then 1973 00:52:13,240 --> 00:52:17,290 guess we'll have to stop here and then next time we will continue