1 00:00:09,340 --> 00:00:13,790 now chapter 11 we skip the chapter 10 2 00:00:13,790 --> 00:00:13,800 now chapter 11 we skip the chapter 10 3 00:00:13,800 --> 00:00:17,040 now chapter 11 we skip the chapter 10 it's about gases I will advise you just 4 00:00:17,040 --> 00:00:17,050 it's about gases I will advise you just 5 00:00:17,050 --> 00:00:23,160 it's about gases I will advise you just to read it it is simple now chapter 11 6 00:00:23,160 --> 00:00:23,170 to read it it is simple now chapter 11 7 00:00:23,170 --> 00:00:25,920 to read it it is simple now chapter 11 is about liquids and intermolecular 8 00:00:25,920 --> 00:00:25,930 is about liquids and intermolecular 9 00:00:25,930 --> 00:00:32,519 is about liquids and intermolecular forces it's again an easy chapter not 10 00:00:32,519 --> 00:00:32,529 forces it's again an easy chapter not 11 00:00:32,529 --> 00:00:37,580 forces it's again an easy chapter not hard I'm sure you will follow and easily 12 00:00:37,580 --> 00:00:37,590 hard I'm sure you will follow and easily 13 00:00:37,590 --> 00:00:46,890 hard I'm sure you will follow and easily now we have three states of matter right 14 00:00:46,890 --> 00:00:46,900 now we have three states of matter right 15 00:00:46,900 --> 00:00:49,590 now we have three states of matter right as I start the chemistry course actually 16 00:00:49,590 --> 00:00:49,600 as I start the chemistry course actually 17 00:00:49,600 --> 00:00:51,570 as I start the chemistry course actually when talk about the states of matter I 18 00:00:51,570 --> 00:00:51,580 when talk about the states of matter I 19 00:00:51,580 --> 00:00:54,360 when talk about the states of matter I say there are two three states and one 20 00:00:54,360 --> 00:00:54,370 say there are two three states and one 21 00:00:54,370 --> 00:00:56,970 say there are two three states and one of them is the solid state the other one 22 00:00:56,970 --> 00:00:56,980 of them is the solid state the other one 23 00:00:56,980 --> 00:01:00,180 of them is the solid state the other one is liquid state and the other is gaseous 24 00:01:00,180 --> 00:01:00,190 is liquid state and the other is gaseous 25 00:01:00,190 --> 00:01:03,780 is liquid state and the other is gaseous state now if you compare these three 26 00:01:03,780 --> 00:01:03,790 state now if you compare these three 27 00:01:03,790 --> 00:01:10,140 state now if you compare these three different states at molecular or atomic 28 00:01:10,140 --> 00:01:10,150 different states at molecular or atomic 29 00:01:10,150 --> 00:01:15,209 different states at molecular or atomic level we actually see this when we have 30 00:01:15,209 --> 00:01:15,219 level we actually see this when we have 31 00:01:15,219 --> 00:01:21,929 level we actually see this when we have a solid as we see here the molecules or 32 00:01:21,929 --> 00:01:21,939 a solid as we see here the molecules or 33 00:01:21,939 --> 00:01:25,380 a solid as we see here the molecules or the ions or the atoms makes the solid 34 00:01:25,380 --> 00:01:25,390 the ions or the atoms makes the solid 35 00:01:25,390 --> 00:01:31,620 the ions or the atoms makes the solid are very regularly arranged in the three 36 00:01:31,620 --> 00:01:31,630 are very regularly arranged in the three 37 00:01:31,630 --> 00:01:36,649 are very regularly arranged in the three dimensions and the solid in fact is hard 38 00:01:36,649 --> 00:01:36,659 dimensions and the solid in fact is hard 39 00:01:36,659 --> 00:01:40,319 dimensions and the solid in fact is hard we can't really change the volume of a 40 00:01:40,319 --> 00:01:40,329 we can't really change the volume of a 41 00:01:40,329 --> 00:01:43,319 we can't really change the volume of a solid by applying pressure if we take a 42 00:01:43,319 --> 00:01:43,329 solid by applying pressure if we take a 43 00:01:43,329 --> 00:01:45,870 solid by applying pressure if we take a solid and put it in a container it will 44 00:01:45,870 --> 00:01:45,880 solid and put it in a container it will 45 00:01:45,880 --> 00:01:49,410 solid and put it in a container it will not fill the container or take the shape 46 00:01:49,410 --> 00:01:49,420 not fill the container or take the shape 47 00:01:49,420 --> 00:01:52,230 not fill the container or take the shape of the container but will just stay as 48 00:01:52,230 --> 00:01:52,240 of the container but will just stay as 49 00:01:52,240 --> 00:01:56,789 of the container but will just stay as it is and the liquid if you take a 50 00:01:56,789 --> 00:01:56,799 it is and the liquid if you take a 51 00:01:56,799 --> 00:02:00,840 it is and the liquid if you take a liquid again apply pressure you can't 52 00:02:00,840 --> 00:02:00,850 liquid again apply pressure you can't 53 00:02:00,850 --> 00:02:03,059 liquid again apply pressure you can't change the volume much off the liquid 54 00:02:03,059 --> 00:02:03,069 change the volume much off the liquid 55 00:02:03,069 --> 00:02:05,760 change the volume much off the liquid that means that the liquid just like 56 00:02:05,760 --> 00:02:05,770 that means that the liquid just like 57 00:02:05,770 --> 00:02:08,969 that means that the liquid just like same as the solid are not compressible I 58 00:02:08,969 --> 00:02:08,979 same as the solid are not compressible I 59 00:02:08,979 --> 00:02:12,860 same as the solid are not compressible I can't change the volume munch but the 60 00:02:12,860 --> 00:02:12,870 can't change the volume munch but the 61 00:02:12,870 --> 00:02:15,780 can't change the volume munch but the liquid will take the shape of the 62 00:02:15,780 --> 00:02:15,790 liquid will take the shape of the 63 00:02:15,790 --> 00:02:19,830 liquid will take the shape of the container that you put in right so 64 00:02:19,830 --> 00:02:19,840 container that you put in right so 65 00:02:19,840 --> 00:02:24,000 container that you put in right so simply you can move and change its shape 66 00:02:24,000 --> 00:02:24,010 simply you can move and change its shape 67 00:02:24,010 --> 00:02:28,289 simply you can move and change its shape easily as a matter of fact now the gas 68 00:02:28,289 --> 00:02:28,299 easily as a matter of fact now the gas 69 00:02:28,299 --> 00:02:31,350 easily as a matter of fact now the gas on the other side if you take a gas and 70 00:02:31,350 --> 00:02:31,360 on the other side if you take a gas and 71 00:02:31,360 --> 00:02:34,949 on the other side if you take a gas and apply pressure we can reduce the volume 72 00:02:34,949 --> 00:02:34,959 apply pressure we can reduce the volume 73 00:02:34,959 --> 00:02:35,789 apply pressure we can reduce the volume easily 74 00:02:35,789 --> 00:02:35,799 easily 75 00:02:35,799 --> 00:02:38,280 easily that means the gases are compressible 76 00:02:38,280 --> 00:02:38,290 that means the gases are compressible 77 00:02:38,290 --> 00:02:41,220 that means the gases are compressible and if you take a gas and put it in a 78 00:02:41,220 --> 00:02:41,230 and if you take a gas and put it in a 79 00:02:41,230 --> 00:02:43,229 and if you take a gas and put it in a container doesn't matter what volume it 80 00:02:43,229 --> 00:02:43,239 container doesn't matter what volume it 81 00:02:43,239 --> 00:02:46,789 container doesn't matter what volume it is it will fill out the whole container 82 00:02:46,789 --> 00:02:46,799 is it will fill out the whole container 83 00:02:46,799 --> 00:02:50,670 is it will fill out the whole container now these observed properties can be 84 00:02:50,670 --> 00:02:50,680 now these observed properties can be 85 00:02:50,680 --> 00:02:55,800 now these observed properties can be explained in terms of intermolecular or 86 00:02:55,800 --> 00:02:55,810 explained in terms of intermolecular or 87 00:02:55,810 --> 00:03:00,270 explained in terms of intermolecular or inter atomic in tyrannic interactions in 88 00:03:00,270 --> 00:03:00,280 inter atomic in tyrannic interactions in 89 00:03:00,280 --> 00:03:01,949 inter atomic in tyrannic interactions in these three different states 90 00:03:01,949 --> 00:03:01,959 these three different states 91 00:03:01,959 --> 00:03:06,559 these three different states we know that the solid in fact the 92 00:03:06,559 --> 00:03:06,569 we know that the solid in fact the 93 00:03:06,569 --> 00:03:09,629 we know that the solid in fact the molecules or the atoms all the ions 94 00:03:09,629 --> 00:03:09,639 molecules or the atoms all the ions 95 00:03:09,639 --> 00:03:11,789 molecules or the atoms all the ions whatever the units makes the solid are 96 00:03:11,789 --> 00:03:11,799 whatever the units makes the solid are 97 00:03:11,799 --> 00:03:15,180 whatever the units makes the solid are very strongly attracted to each other 98 00:03:15,180 --> 00:03:15,190 very strongly attracted to each other 99 00:03:15,190 --> 00:03:18,809 very strongly attracted to each other that means intermolecular forces are 100 00:03:18,809 --> 00:03:18,819 that means intermolecular forces are 101 00:03:18,819 --> 00:03:23,750 that means intermolecular forces are very very high so that is why the solids 102 00:03:23,750 --> 00:03:23,760 very very high so that is why the solids 103 00:03:23,760 --> 00:03:27,210 very very high so that is why the solids does not change it is shape when you 104 00:03:27,210 --> 00:03:27,220 does not change it is shape when you 105 00:03:27,220 --> 00:03:29,069 does not change it is shape when you pour it when you put it in a container 106 00:03:29,069 --> 00:03:29,079 pour it when you put it in a container 107 00:03:29,079 --> 00:03:35,069 pour it when you put it in a container it will just stay as it is now what doll 108 00:03:35,069 --> 00:03:35,079 it will just stay as it is now what doll 109 00:03:35,079 --> 00:03:38,250 it will just stay as it is now what doll what do the molecules or the units in a 110 00:03:38,250 --> 00:03:38,260 what do the molecules or the units in a 111 00:03:38,260 --> 00:03:41,539 what do the molecules or the units in a solid they are not stationary right in 112 00:03:41,539 --> 00:03:41,549 solid they are not stationary right in 113 00:03:41,549 --> 00:03:44,400 solid they are not stationary right in solid they move but they make vibration 114 00:03:44,400 --> 00:03:44,410 solid they move but they make vibration 115 00:03:44,410 --> 00:03:47,670 solid they move but they make vibration emotions simply like this but they're 116 00:03:47,670 --> 00:03:47,680 emotions simply like this but they're 117 00:03:47,680 --> 00:03:52,229 emotions simply like this but they're more less the average point do not 118 00:03:52,229 --> 00:03:52,239 more less the average point do not 119 00:03:52,239 --> 00:03:54,420 more less the average point do not change it just just move like this make 120 00:03:54,420 --> 00:03:54,430 change it just just move like this make 121 00:03:54,430 --> 00:03:56,550 change it just just move like this make vibration of motions in the solid but 122 00:03:56,550 --> 00:03:56,560 vibration of motions in the solid but 123 00:03:56,560 --> 00:03:58,110 vibration of motions in the solid but they cannot separate from one another 124 00:03:58,110 --> 00:03:58,120 they cannot separate from one another 125 00:03:58,120 --> 00:04:00,720 they cannot separate from one another why because they are attracted each 126 00:04:00,720 --> 00:04:00,730 why because they are attracted each 127 00:04:00,730 --> 00:04:02,699 why because they are attracted each other that means there's a very strong 128 00:04:02,699 --> 00:04:02,709 other that means there's a very strong 129 00:04:02,709 --> 00:04:05,879 other that means there's a very strong attraction force between the molecules 130 00:04:05,879 --> 00:04:05,889 attraction force between the molecules 131 00:04:05,889 --> 00:04:08,580 attraction force between the molecules of the solids or the units of the 132 00:04:08,580 --> 00:04:08,590 of the solids or the units of the 133 00:04:08,590 --> 00:04:11,640 of the solids or the units of the solvent is a matter of fact now the 134 00:04:11,640 --> 00:04:11,650 solvent is a matter of fact now the 135 00:04:11,650 --> 00:04:15,270 solvent is a matter of fact now the other things is the distances between 136 00:04:15,270 --> 00:04:15,280 other things is the distances between 137 00:04:15,280 --> 00:04:18,509 other things is the distances between the molecules of the solid in the solid 138 00:04:18,509 --> 00:04:18,519 the molecules of the solid in the solid 139 00:04:18,519 --> 00:04:20,279 the molecules of the solid in the solid is not much that means there's not much 140 00:04:20,279 --> 00:04:20,289 is not much that means there's not much 141 00:04:20,289 --> 00:04:23,670 is not much that means there's not much space between the solid molecules or the 142 00:04:23,670 --> 00:04:23,680 space between the solid molecules or the 143 00:04:23,680 --> 00:04:26,939 space between the solid molecules or the solid units so that's why the solids are 144 00:04:26,939 --> 00:04:26,949 solid units so that's why the solids are 145 00:04:26,949 --> 00:04:30,060 solid units so that's why the solids are not compressible that means you can't 146 00:04:30,060 --> 00:04:30,070 not compressible that means you can't 147 00:04:30,070 --> 00:04:33,810 not compressible that means you can't really apply pressure and change the 148 00:04:33,810 --> 00:04:33,820 really apply pressure and change the 149 00:04:33,820 --> 00:04:35,610 really apply pressure and change the volume reduce the volume of the solid 150 00:04:35,610 --> 00:04:35,620 volume reduce the volume of the solid 151 00:04:35,620 --> 00:04:36,990 volume reduce the volume of the solid there's not much space actually 152 00:04:36,990 --> 00:04:37,000 there's not much space actually 153 00:04:37,000 --> 00:04:39,780 there's not much space actually between the units molecules or the atoms 154 00:04:39,780 --> 00:04:39,790 between the units molecules or the atoms 155 00:04:39,790 --> 00:04:42,210 between the units molecules or the atoms of the solid is a matter of fact now if 156 00:04:42,210 --> 00:04:42,220 of the solid is a matter of fact now if 157 00:04:42,220 --> 00:04:45,330 of the solid is a matter of fact now if you go to the liquid the attraction 158 00:04:45,330 --> 00:04:45,340 you go to the liquid the attraction 159 00:04:45,340 --> 00:04:47,760 you go to the liquid the attraction between the molecules of the liquids are 160 00:04:47,760 --> 00:04:47,770 between the molecules of the liquids are 161 00:04:47,770 --> 00:04:51,510 between the molecules of the liquids are also very strong because the liquids 162 00:04:51,510 --> 00:04:51,520 also very strong because the liquids 163 00:04:51,520 --> 00:04:55,170 also very strong because the liquids cannot simply leave the liquid state and 164 00:04:55,170 --> 00:04:55,180 cannot simply leave the liquid state and 165 00:04:55,180 --> 00:04:57,120 cannot simply leave the liquid state and go into the gaseous state or other state 166 00:04:57,120 --> 00:04:57,130 go into the gaseous state or other state 167 00:04:57,130 --> 00:04:59,010 go into the gaseous state or other state they have to stay together they have to 168 00:04:59,010 --> 00:04:59,020 they have to stay together they have to 169 00:04:59,020 --> 00:05:00,750 they have to stay together they have to stay together what keeps them together 170 00:05:00,750 --> 00:05:00,760 stay together what keeps them together 171 00:05:00,760 --> 00:05:03,510 stay together what keeps them together actually the intermolecular force of 172 00:05:03,510 --> 00:05:03,520 actually the intermolecular force of 173 00:05:03,520 --> 00:05:06,030 actually the intermolecular force of attraction right intermolecular force of 174 00:05:06,030 --> 00:05:06,040 attraction right intermolecular force of 175 00:05:06,040 --> 00:05:08,580 attraction right intermolecular force of attraction but since the liquid 176 00:05:08,580 --> 00:05:08,590 attraction but since the liquid 177 00:05:08,590 --> 00:05:13,260 attraction but since the liquid molecules are moving freely as they 178 00:05:13,260 --> 00:05:13,270 molecules are moving freely as they 179 00:05:13,270 --> 00:05:15,750 molecules are moving freely as they touch each other like this you can 180 00:05:15,750 --> 00:05:15,760 touch each other like this you can 181 00:05:15,760 --> 00:05:17,820 touch each other like this you can change the shape of the liquid easily 182 00:05:17,820 --> 00:05:17,830 change the shape of the liquid easily 183 00:05:17,830 --> 00:05:20,909 change the shape of the liquid easily actually the shape of the liquid will be 184 00:05:20,909 --> 00:05:20,919 actually the shape of the liquid will be 185 00:05:20,919 --> 00:05:22,560 actually the shape of the liquid will be the same as the shape of the container 186 00:05:22,560 --> 00:05:22,570 the same as the shape of the container 187 00:05:22,570 --> 00:05:25,560 the same as the shape of the container that you put in right but they will not 188 00:05:25,560 --> 00:05:25,570 that you put in right but they will not 189 00:05:25,570 --> 00:05:27,900 that you put in right but they will not fill in the whole volume of the 190 00:05:27,900 --> 00:05:27,910 fill in the whole volume of the 191 00:05:27,910 --> 00:05:29,820 fill in the whole volume of the container as a matter of fact so what we 192 00:05:29,820 --> 00:05:29,830 container as a matter of fact so what we 193 00:05:29,830 --> 00:05:32,970 container as a matter of fact so what we say that the intermolecular forces or 194 00:05:32,970 --> 00:05:32,980 say that the intermolecular forces or 195 00:05:32,980 --> 00:05:35,040 say that the intermolecular forces or attraction forces between the liquid 196 00:05:35,040 --> 00:05:35,050 attraction forces between the liquid 197 00:05:35,050 --> 00:05:36,900 attraction forces between the liquid molecules or the unit that make the 198 00:05:36,900 --> 00:05:36,910 molecules or the unit that make the 199 00:05:36,910 --> 00:05:40,409 molecules or the unit that make the liquid are weaker than this solid but 200 00:05:40,409 --> 00:05:40,419 liquid are weaker than this solid but 201 00:05:40,419 --> 00:05:43,830 liquid are weaker than this solid but they are pretty strong still strong that 202 00:05:43,830 --> 00:05:43,840 they are pretty strong still strong that 203 00:05:43,840 --> 00:05:46,080 they are pretty strong still strong that the liquid stays together that means it 204 00:05:46,080 --> 00:05:46,090 the liquid stays together that means it 205 00:05:46,090 --> 00:05:48,090 the liquid stays together that means it in the liquid state now when you go to 206 00:05:48,090 --> 00:05:48,100 in the liquid state now when you go to 207 00:05:48,100 --> 00:05:53,600 in the liquid state now when you go to the gas the molecules are simply moving 208 00:05:53,600 --> 00:05:53,610 the gas the molecules are simply moving 209 00:05:53,610 --> 00:05:56,700 the gas the molecules are simply moving freely in three-dimensional space like 210 00:05:56,700 --> 00:05:56,710 freely in three-dimensional space like 211 00:05:56,710 --> 00:06:00,600 freely in three-dimensional space like this why because the attraction between 212 00:06:00,600 --> 00:06:00,610 this why because the attraction between 213 00:06:00,610 --> 00:06:06,080 this why because the attraction between the gas molecules is very very weak 214 00:06:06,080 --> 00:06:06,090 the gas molecules is very very weak 215 00:06:06,090 --> 00:06:09,590 the gas molecules is very very weak actually if you consider the ideal gas 216 00:06:09,590 --> 00:06:09,600 actually if you consider the ideal gas 217 00:06:09,600 --> 00:06:12,870 actually if you consider the ideal gas in the ideal gases we assume that the 218 00:06:12,870 --> 00:06:12,880 in the ideal gases we assume that the 219 00:06:12,880 --> 00:06:16,409 in the ideal gases we assume that the intermolecular attraction is zero in a 220 00:06:16,409 --> 00:06:16,419 intermolecular attraction is zero in a 221 00:06:16,419 --> 00:06:18,690 intermolecular attraction is zero in a gaseous state there's no attractions so 222 00:06:18,690 --> 00:06:18,700 gaseous state there's no attractions so 223 00:06:18,700 --> 00:06:21,530 gaseous state there's no attractions so every gas molecules moves in 224 00:06:21,530 --> 00:06:21,540 every gas molecules moves in 225 00:06:21,540 --> 00:06:23,520 every gas molecules moves in three-dimensional space freely as a 226 00:06:23,520 --> 00:06:23,530 three-dimensional space freely as a 227 00:06:23,530 --> 00:06:27,090 three-dimensional space freely as a matter of fact like this now also there 228 00:06:27,090 --> 00:06:27,100 matter of fact like this now also there 229 00:06:27,100 --> 00:06:30,600 matter of fact like this now also there is a lot of space between the gas 230 00:06:30,600 --> 00:06:30,610 is a lot of space between the gas 231 00:06:30,610 --> 00:06:33,360 is a lot of space between the gas molecules right so if you simply 232 00:06:33,360 --> 00:06:33,370 molecules right so if you simply 233 00:06:33,370 --> 00:06:37,409 molecules right so if you simply compress the gas Moloch gases sample 234 00:06:37,409 --> 00:06:37,419 compress the gas Moloch gases sample 235 00:06:37,419 --> 00:06:39,860 compress the gas Moloch gases sample apply pressure you can change the volume 236 00:06:39,860 --> 00:06:39,870 apply pressure you can change the volume 237 00:06:39,870 --> 00:06:42,719 apply pressure you can change the volume but if you increase the volume since the 238 00:06:42,719 --> 00:06:42,729 but if you increase the volume since the 239 00:06:42,729 --> 00:06:44,520 but if you increase the volume since the gas molecules are moving they will fill 240 00:06:44,520 --> 00:06:44,530 gas molecules are moving they will fill 241 00:06:44,530 --> 00:06:47,460 gas molecules are moving they will fill out the whole container right they will 242 00:06:47,460 --> 00:06:47,470 out the whole container right they will 243 00:06:47,470 --> 00:06:49,800 out the whole container right they will fill out the whole container so that 244 00:06:49,800 --> 00:06:49,810 fill out the whole container so that 245 00:06:49,810 --> 00:06:50,640 fill out the whole container so that means 246 00:06:50,640 --> 00:06:50,650 means 247 00:06:50,650 --> 00:06:55,740 means the attractions between the molecules in 248 00:06:55,740 --> 00:06:55,750 the attractions between the molecules in 249 00:06:55,750 --> 00:06:58,740 the attractions between the molecules in the solid is very strong if the liquid 250 00:06:58,740 --> 00:06:58,750 the solid is very strong if the liquid 251 00:06:58,750 --> 00:07:01,230 the solid is very strong if the liquid is still strong but not as strong as 252 00:07:01,230 --> 00:07:01,240 is still strong but not as strong as 253 00:07:01,240 --> 00:07:05,159 is still strong but not as strong as solid and then for the gas the 254 00:07:05,159 --> 00:07:05,169 solid and then for the gas the 255 00:07:05,169 --> 00:07:07,950 solid and then for the gas the attractions is very very weak as a 256 00:07:07,950 --> 00:07:07,960 attractions is very very weak as a 257 00:07:07,960 --> 00:07:10,560 attractions is very very weak as a matter of fact almost negligible right 258 00:07:10,560 --> 00:07:10,570 matter of fact almost negligible right 259 00:07:10,570 --> 00:07:15,800 matter of fact almost negligible right this is how we describe the three states 260 00:07:15,800 --> 00:07:15,810 this is how we describe the three states 261 00:07:15,810 --> 00:07:19,530 this is how we describe the three states and molecular level properties and these 262 00:07:19,530 --> 00:07:19,540 and molecular level properties and these 263 00:07:19,540 --> 00:07:24,020 and molecular level properties and these actually explains why we observe those 264 00:07:24,020 --> 00:07:24,030 actually explains why we observe those 265 00:07:24,030 --> 00:07:26,610 actually explains why we observe those physical properties of the solids 266 00:07:26,610 --> 00:07:26,620 physical properties of the solids 267 00:07:26,620 --> 00:07:28,860 physical properties of the solids liquids and the gases that means change 268 00:07:28,860 --> 00:07:28,870 liquids and the gases that means change 269 00:07:28,870 --> 00:07:32,070 liquids and the gases that means change in volume and compressibility and so on 270 00:07:32,070 --> 00:07:32,080 in volume and compressibility and so on 271 00:07:32,080 --> 00:07:35,189 in volume and compressibility and so on now let's see what we have okay this 272 00:07:35,189 --> 00:07:35,199 now let's see what we have okay this 273 00:07:35,199 --> 00:07:38,400 now let's see what we have okay this this explains very shortly those 274 00:07:38,400 --> 00:07:38,410 this explains very shortly those 275 00:07:38,410 --> 00:07:41,010 this explains very shortly those properties of gases different states of 276 00:07:41,010 --> 00:07:41,020 properties of gases different states of 277 00:07:41,020 --> 00:07:43,740 properties of gases different states of matter here it seems both volume and the 278 00:07:43,740 --> 00:07:43,750 matter here it seems both volume and the 279 00:07:43,750 --> 00:07:45,240 matter here it seems both volume and the shape of the container we say that 280 00:07:45,240 --> 00:07:45,250 shape of the container we say that 281 00:07:45,250 --> 00:07:48,050 shape of the container we say that expands to fill the container and is 282 00:07:48,050 --> 00:07:48,060 expands to fill the container and is 283 00:07:48,060 --> 00:07:51,900 expands to fill the container and is compressible and flows readily diffusion 284 00:07:51,900 --> 00:07:51,910 compressible and flows readily diffusion 285 00:07:51,910 --> 00:07:54,570 compressible and flows readily diffusion within the gas occurs rapidly this is 286 00:07:54,570 --> 00:07:54,580 within the gas occurs rapidly this is 287 00:07:54,580 --> 00:07:56,760 within the gas occurs rapidly this is the gas phase and all of these are 288 00:07:56,760 --> 00:07:56,770 the gas phase and all of these are 289 00:07:56,770 --> 00:08:00,659 the gas phase and all of these are explained with the model where you have 290 00:08:00,659 --> 00:08:00,669 explained with the model where you have 291 00:08:00,669 --> 00:08:02,879 explained with the model where you have the gas molecules are freely moving 292 00:08:02,879 --> 00:08:02,889 the gas molecules are freely moving 293 00:08:02,889 --> 00:08:05,040 the gas molecules are freely moving attractions between the gas molecules is 294 00:08:05,040 --> 00:08:05,050 attractions between the gas molecules is 295 00:08:05,050 --> 00:08:07,770 attractions between the gas molecules is very very weak as a matter of fact now 296 00:08:07,770 --> 00:08:07,780 very very weak as a matter of fact now 297 00:08:07,780 --> 00:08:10,200 very very weak as a matter of fact now in the liquids this gain assumes the 298 00:08:10,200 --> 00:08:10,210 in the liquids this gain assumes the 299 00:08:10,210 --> 00:08:13,440 in the liquids this gain assumes the shape of the portion of the container it 300 00:08:13,440 --> 00:08:13,450 shape of the portion of the container it 301 00:08:13,450 --> 00:08:16,020 shape of the portion of the container it occupies does not expand the fill it's 302 00:08:16,020 --> 00:08:16,030 occupies does not expand the fill it's 303 00:08:16,030 --> 00:08:17,909 occupies does not expand the fill it's all container here it fills the whole 304 00:08:17,909 --> 00:08:17,919 all container here it fills the whole 305 00:08:17,919 --> 00:08:21,830 all container here it fills the whole container and is virtually 306 00:08:21,830 --> 00:08:21,840 container and is virtually 307 00:08:21,840 --> 00:08:23,760 container and is virtually incompressible not much space between 308 00:08:23,760 --> 00:08:23,770 incompressible not much space between 309 00:08:23,770 --> 00:08:25,830 incompressible not much space between the liquid molecules Falls readily 310 00:08:25,830 --> 00:08:25,840 the liquid molecules Falls readily 311 00:08:25,840 --> 00:08:27,870 the liquid molecules Falls readily diffusion within the liquid occurs 312 00:08:27,870 --> 00:08:27,880 diffusion within the liquid occurs 313 00:08:27,880 --> 00:08:30,900 diffusion within the liquid occurs slowly much slower than the gas in this 314 00:08:30,900 --> 00:08:30,910 slowly much slower than the gas in this 315 00:08:30,910 --> 00:08:33,779 slowly much slower than the gas in this solid retains own shape and volume 316 00:08:33,779 --> 00:08:33,789 solid retains own shape and volume 317 00:08:33,789 --> 00:08:37,290 solid retains own shape and volume doesn't change and does not expand to 318 00:08:37,290 --> 00:08:37,300 doesn't change and does not expand to 319 00:08:37,300 --> 00:08:39,800 doesn't change and does not expand to fill its container it's virtually 320 00:08:39,800 --> 00:08:39,810 fill its container it's virtually 321 00:08:39,810 --> 00:08:43,290 fill its container it's virtually incompressible does not flow diffusion 322 00:08:43,290 --> 00:08:43,300 incompressible does not flow diffusion 323 00:08:43,300 --> 00:08:45,720 incompressible does not flow diffusion within the solid occurs extremely slow 324 00:08:45,720 --> 00:08:45,730 within the solid occurs extremely slow 325 00:08:45,730 --> 00:08:48,570 within the solid occurs extremely slow very very slow so this simply gives you 326 00:08:48,570 --> 00:08:48,580 very very slow so this simply gives you 327 00:08:48,580 --> 00:08:52,079 very very slow so this simply gives you idea about three different states as a 328 00:08:52,079 --> 00:08:52,089 idea about three different states as a 329 00:08:52,089 --> 00:09:00,760 idea about three different states as a matter of fact winters day yeah 330 00:09:00,760 --> 00:09:00,770 331 00:09:00,770 --> 00:09:03,710 how can we explain these behavior 332 00:09:03,710 --> 00:09:03,720 how can we explain these behavior 333 00:09:03,720 --> 00:09:08,390 how can we explain these behavior actually here it says the answer to this 334 00:09:08,390 --> 00:09:08,400 actually here it says the answer to this 335 00:09:08,400 --> 00:09:12,350 actually here it says the answer to this question largely relies on the balance 336 00:09:12,350 --> 00:09:12,360 question largely relies on the balance 337 00:09:12,360 --> 00:09:14,750 question largely relies on the balance between the kinetic energies of the 338 00:09:14,750 --> 00:09:14,760 between the kinetic energies of the 339 00:09:14,760 --> 00:09:18,260 between the kinetic energies of the particles and inter particle energies of 340 00:09:18,260 --> 00:09:18,270 particles and inter particle energies of 341 00:09:18,270 --> 00:09:22,520 particles and inter particle energies of attraction now this is again can be 342 00:09:22,520 --> 00:09:22,530 attraction now this is again can be 343 00:09:22,530 --> 00:09:26,830 attraction now this is again can be explained as following we have the 344 00:09:26,830 --> 00:09:26,840 explained as following we have the 345 00:09:26,840 --> 00:09:30,320 explained as following we have the attraction between two molecules like 346 00:09:30,320 --> 00:09:30,330 attraction between two molecules like 347 00:09:30,330 --> 00:09:35,030 attraction between two molecules like this and we also have the kinetic energy 348 00:09:35,030 --> 00:09:35,040 this and we also have the kinetic energy 349 00:09:35,040 --> 00:09:37,820 this and we also have the kinetic energy of the molecules in the solid state they 350 00:09:37,820 --> 00:09:37,830 of the molecules in the solid state they 351 00:09:37,830 --> 00:09:40,240 of the molecules in the solid state they simply move like this vibrational type 352 00:09:40,240 --> 00:09:40,250 simply move like this vibrational type 353 00:09:40,250 --> 00:09:42,910 simply move like this vibrational type motions but they have kinetic energies 354 00:09:42,910 --> 00:09:42,920 motions but they have kinetic energies 355 00:09:42,920 --> 00:09:47,120 motions but they have kinetic energies in the liquid they can move freely by 356 00:09:47,120 --> 00:09:47,130 in the liquid they can move freely by 357 00:09:47,130 --> 00:09:48,620 in the liquid they can move freely by touching each other like this they're 358 00:09:48,620 --> 00:09:48,630 touching each other like this they're 359 00:09:48,630 --> 00:09:52,160 touching each other like this they're not separate in a gas they are more free 360 00:09:52,160 --> 00:09:52,170 not separate in a gas they are more free 361 00:09:52,170 --> 00:09:55,990 not separate in a gas they are more free to move so simply we can say that the 362 00:09:55,990 --> 00:09:56,000 to move so simply we can say that the 363 00:09:56,000 --> 00:10:00,460 to move so simply we can say that the attraction forces in this solid is 364 00:10:00,460 --> 00:10:00,470 attraction forces in this solid is 365 00:10:00,470 --> 00:10:03,520 attraction forces in this solid is greater than the kinetic energy of the 366 00:10:03,520 --> 00:10:03,530 greater than the kinetic energy of the 367 00:10:03,530 --> 00:10:04,850 greater than the kinetic energy of the molecules 368 00:10:04,850 --> 00:10:04,860 molecules 369 00:10:04,860 --> 00:10:07,910 molecules therefore the molecules cannot simply 370 00:10:07,910 --> 00:10:07,920 therefore the molecules cannot simply 371 00:10:07,920 --> 00:10:11,390 therefore the molecules cannot simply break off break that attractions and 372 00:10:11,390 --> 00:10:11,400 break off break that attractions and 373 00:10:11,400 --> 00:10:13,660 break off break that attractions and become free right so that means 374 00:10:13,660 --> 00:10:13,670 become free right so that means 375 00:10:13,670 --> 00:10:16,670 become free right so that means attraction forces in the solid greater 376 00:10:16,670 --> 00:10:16,680 attraction forces in the solid greater 377 00:10:16,680 --> 00:10:19,100 attraction forces in the solid greater than the kinetic energy now if you go to 378 00:10:19,100 --> 00:10:19,110 than the kinetic energy now if you go to 379 00:10:19,110 --> 00:10:22,190 than the kinetic energy now if you go to the liquid in this case the attraction 380 00:10:22,190 --> 00:10:22,200 the liquid in this case the attraction 381 00:10:22,200 --> 00:10:25,490 the liquid in this case the attraction forces are about the kinetic energy or a 382 00:10:25,490 --> 00:10:25,500 forces are about the kinetic energy or a 383 00:10:25,500 --> 00:10:27,680 forces are about the kinetic energy or a little bit less than kinetic energy why 384 00:10:27,680 --> 00:10:27,690 little bit less than kinetic energy why 385 00:10:27,690 --> 00:10:32,120 little bit less than kinetic energy why because the molecules in the liquid can 386 00:10:32,120 --> 00:10:32,130 because the molecules in the liquid can 387 00:10:32,130 --> 00:10:35,780 because the molecules in the liquid can go by and move in the liquid freely as a 388 00:10:35,780 --> 00:10:35,790 go by and move in the liquid freely as a 389 00:10:35,790 --> 00:10:39,520 go by and move in the liquid freely as a matter of fact right they simply just 390 00:10:39,520 --> 00:10:39,530 matter of fact right they simply just 391 00:10:39,530 --> 00:10:43,040 matter of fact right they simply just break even with the attraction forces in 392 00:10:43,040 --> 00:10:43,050 break even with the attraction forces in 393 00:10:43,050 --> 00:10:45,770 break even with the attraction forces in fact attraction energy between the 394 00:10:45,770 --> 00:10:45,780 fact attraction energy between the 395 00:10:45,780 --> 00:10:48,140 fact attraction energy between the molecules but if you go in the gaseous 396 00:10:48,140 --> 00:10:48,150 molecules but if you go in the gaseous 397 00:10:48,150 --> 00:10:52,010 molecules but if you go in the gaseous state kinetic energy is much greater 398 00:10:52,010 --> 00:10:52,020 state kinetic energy is much greater 399 00:10:52,020 --> 00:10:55,190 state kinetic energy is much greater than the energy of attraction between 400 00:10:55,190 --> 00:10:55,200 than the energy of attraction between 401 00:10:55,200 --> 00:10:58,190 than the energy of attraction between the molecules as a matter of fact right 402 00:10:58,190 --> 00:10:58,200 the molecules as a matter of fact right 403 00:10:58,200 --> 00:11:00,710 the molecules as a matter of fact right therefore the molecules simply move 404 00:11:00,710 --> 00:11:00,720 therefore the molecules simply move 405 00:11:00,720 --> 00:11:03,610 therefore the molecules simply move freely from one another and that is the 406 00:11:03,610 --> 00:11:03,620 freely from one another and that is the 407 00:11:03,620 --> 00:11:07,100 freely from one another and that is the gaseous state so this is what try to 408 00:11:07,100 --> 00:11:07,110 gaseous state so this is what try to 409 00:11:07,110 --> 00:11:08,840 gaseous state so this is what try to explain that here is the kinetic 410 00:11:08,840 --> 00:11:08,850 explain that here is the kinetic 411 00:11:08,850 --> 00:11:10,610 explain that here is the kinetic energies in the gas phase is much 412 00:11:10,610 --> 00:11:10,620 energies in the gas phase is much 413 00:11:10,620 --> 00:11:11,570 energies in the gas phase is much greater than the 414 00:11:11,570 --> 00:11:11,580 greater than the 415 00:11:11,580 --> 00:11:13,790 greater than the fraction energies of attraction in the 416 00:11:13,790 --> 00:11:13,800 fraction energies of attraction in the 417 00:11:13,800 --> 00:11:16,430 fraction energies of attraction in the liquid case comparable kinetic energies 418 00:11:16,430 --> 00:11:16,440 liquid case comparable kinetic energies 419 00:11:16,440 --> 00:11:18,350 liquid case comparable kinetic energies and the energies of attraction solid 420 00:11:18,350 --> 00:11:18,360 and the energies of attraction solid 421 00:11:18,360 --> 00:11:20,420 and the energies of attraction solid energies of attractions is greater than 422 00:11:20,420 --> 00:11:20,430 energies of attractions is greater than 423 00:11:20,430 --> 00:11:22,130 energies of attractions is greater than the kinetic energies so this is it 424 00:11:22,130 --> 00:11:22,140 the kinetic energies so this is it 425 00:11:22,140 --> 00:11:26,870 the kinetic energies so this is it now here is a question how can we 426 00:11:26,870 --> 00:11:26,880 now here is a question how can we 427 00:11:26,880 --> 00:11:28,520 now here is a question how can we increase the kinetic energy of the 428 00:11:28,520 --> 00:11:28,530 increase the kinetic energy of the 429 00:11:28,530 --> 00:11:36,130 increase the kinetic energy of the molecules that means by increase in 430 00:11:36,130 --> 00:11:36,140 molecules that means by increase in 431 00:11:36,140 --> 00:11:39,080 molecules that means by increase in temperature yes if you just give heat to 432 00:11:39,080 --> 00:11:39,090 temperature yes if you just give heat to 433 00:11:39,090 --> 00:11:40,550 temperature yes if you just give heat to the system temperature will increase 434 00:11:40,550 --> 00:11:40,560 the system temperature will increase 435 00:11:40,560 --> 00:11:42,830 the system temperature will increase when the temperature increases that 436 00:11:42,830 --> 00:11:42,840 when the temperature increases that 437 00:11:42,840 --> 00:11:45,440 when the temperature increases that means that the kinetic energy of the 438 00:11:45,440 --> 00:11:45,450 means that the kinetic energy of the 439 00:11:45,450 --> 00:11:47,000 means that the kinetic energy of the molecules will increase in three 440 00:11:47,000 --> 00:11:47,010 molecules will increase in three 441 00:11:47,010 --> 00:11:47,690 molecules will increase in three different states 442 00:11:47,690 --> 00:11:47,700 different states 443 00:11:47,700 --> 00:11:50,420 different states so what does that means that means if I 444 00:11:50,420 --> 00:11:50,430 so what does that means that means if I 445 00:11:50,430 --> 00:11:54,140 so what does that means that means if I take a solid which have the kinetic 446 00:11:54,140 --> 00:11:54,150 take a solid which have the kinetic 447 00:11:54,150 --> 00:11:57,520 take a solid which have the kinetic energies actually less than the 448 00:11:57,520 --> 00:11:57,530 energies actually less than the 449 00:11:57,530 --> 00:12:02,030 energies actually less than the attraction energy is right and heat the 450 00:12:02,030 --> 00:12:02,040 attraction energy is right and heat the 451 00:12:02,040 --> 00:12:03,410 attraction energy is right and heat the solid what will happen the kinetic 452 00:12:03,410 --> 00:12:03,420 solid what will happen the kinetic 453 00:12:03,420 --> 00:12:05,000 solid what will happen the kinetic energy will increase and I will get to 454 00:12:05,000 --> 00:12:05,010 energy will increase and I will get to 455 00:12:05,010 --> 00:12:06,440 energy will increase and I will get to the point where the kinetic energy will 456 00:12:06,440 --> 00:12:06,450 the point where the kinetic energy will 457 00:12:06,450 --> 00:12:08,030 the point where the kinetic energy will be greater than the attraction energies 458 00:12:08,030 --> 00:12:08,040 be greater than the attraction energies 459 00:12:08,040 --> 00:12:09,980 be greater than the attraction energies what does that means that means the 460 00:12:09,980 --> 00:12:09,990 what does that means that means the 461 00:12:09,990 --> 00:12:14,050 what does that means that means the solid will go from solid to the liquid 462 00:12:14,050 --> 00:12:14,060 solid will go from solid to the liquid 463 00:12:14,060 --> 00:12:16,220 solid will go from solid to the liquid state that means there's going to be a 464 00:12:16,220 --> 00:12:16,230 state that means there's going to be a 465 00:12:16,230 --> 00:12:18,590 state that means there's going to be a transition between the stage the phase 466 00:12:18,590 --> 00:12:18,600 transition between the stage the phase 467 00:12:18,600 --> 00:12:21,710 transition between the stage the phase now if you take that liquid in fact and 468 00:12:21,710 --> 00:12:21,720 now if you take that liquid in fact and 469 00:12:21,720 --> 00:12:24,170 now if you take that liquid in fact and keep heating it give heat and the 470 00:12:24,170 --> 00:12:24,180 keep heating it give heat and the 471 00:12:24,180 --> 00:12:25,460 keep heating it give heat and the temperature increases as temperature 472 00:12:25,460 --> 00:12:25,470 temperature increases as temperature 473 00:12:25,470 --> 00:12:27,680 temperature increases as temperature increases the kinetic energy of the 474 00:12:27,680 --> 00:12:27,690 increases the kinetic energy of the 475 00:12:27,690 --> 00:12:29,630 increases the kinetic energy of the molecule increases increases and now 476 00:12:29,630 --> 00:12:29,640 molecule increases increases and now 477 00:12:29,640 --> 00:12:31,310 molecule increases increases and now they will be a point where the kinetic 478 00:12:31,310 --> 00:12:31,320 they will be a point where the kinetic 479 00:12:31,320 --> 00:12:33,260 they will be a point where the kinetic energy of the molecule will be much 480 00:12:33,260 --> 00:12:33,270 energy of the molecule will be much 481 00:12:33,270 --> 00:12:36,710 energy of the molecule will be much higher than the attraction energy 482 00:12:36,710 --> 00:12:36,720 higher than the attraction energy 483 00:12:36,720 --> 00:12:38,540 higher than the attraction energy between the molecules what does that 484 00:12:38,540 --> 00:12:38,550 between the molecules what does that 485 00:12:38,550 --> 00:12:41,180 between the molecules what does that means that the molecules will simply 486 00:12:41,180 --> 00:12:41,190 means that the molecules will simply 487 00:12:41,190 --> 00:12:43,010 means that the molecules will simply leave the liquid state will go into the 488 00:12:43,010 --> 00:12:43,020 leave the liquid state will go into the 489 00:12:43,020 --> 00:12:45,080 leave the liquid state will go into the gaseous state right will go into the 490 00:12:45,080 --> 00:12:45,090 gaseous state right will go into the 491 00:12:45,090 --> 00:12:47,060 gaseous state right will go into the gaseous state so in that case it will be 492 00:12:47,060 --> 00:12:47,070 gaseous state so in that case it will be 493 00:12:47,070 --> 00:12:49,640 gaseous state so in that case it will be simply evaporation another change of the 494 00:12:49,640 --> 00:12:49,650 simply evaporation another change of the 495 00:12:49,650 --> 00:12:52,700 simply evaporation another change of the state so we can simply say that the 496 00:12:52,700 --> 00:12:52,710 state so we can simply say that the 497 00:12:52,710 --> 00:12:54,890 state so we can simply say that the kinetic energy at the same temperature 498 00:12:54,890 --> 00:12:54,900 kinetic energy at the same temperature 499 00:12:54,900 --> 00:12:59,270 kinetic energy at the same temperature if I have gas liquid and solid I can 500 00:12:59,270 --> 00:12:59,280 if I have gas liquid and solid I can 501 00:12:59,280 --> 00:13:01,160 if I have gas liquid and solid I can simply say this kinetic energy of the 502 00:13:01,160 --> 00:13:01,170 simply say this kinetic energy of the 503 00:13:01,170 --> 00:13:03,170 simply say this kinetic energy of the molecules highest in the liquid in the 504 00:13:03,170 --> 00:13:03,180 molecules highest in the liquid in the 505 00:13:03,180 --> 00:13:06,590 molecules highest in the liquid in the gas and then lower much lower in the 506 00:13:06,590 --> 00:13:06,600 gas and then lower much lower in the 507 00:13:06,600 --> 00:13:09,770 gas and then lower much lower in the liquid but much lower in the solid state 508 00:13:09,770 --> 00:13:09,780 liquid but much lower in the solid state 509 00:13:09,780 --> 00:13:18,590 liquid but much lower in the solid state right in a solid state now all we said 510 00:13:18,590 --> 00:13:18,600 right in a solid state now all we said 511 00:13:18,600 --> 00:13:23,330 right in a solid state now all we said so far attraction energies that means 512 00:13:23,330 --> 00:13:23,340 so far attraction energies that means 513 00:13:23,340 --> 00:13:25,460 so far attraction energies that means there is an attraction force 514 00:13:25,460 --> 00:13:25,470 there is an attraction force 515 00:13:25,470 --> 00:13:27,440 there is an attraction force between the molecules so now let's look 516 00:13:27,440 --> 00:13:27,450 between the molecules so now let's look 517 00:13:27,450 --> 00:13:30,950 between the molecules so now let's look at what kind of attractions between the 518 00:13:30,950 --> 00:13:30,960 at what kind of attractions between the 519 00:13:30,960 --> 00:13:34,100 at what kind of attractions between the molecules are possible and we call these 520 00:13:34,100 --> 00:13:34,110 molecules are possible and we call these 521 00:13:34,110 --> 00:13:36,590 molecules are possible and we call these forces intermolecular forces 522 00:13:36,590 --> 00:13:36,600 forces intermolecular forces 523 00:13:36,600 --> 00:13:39,760 forces intermolecular forces intermolecular forces now 524 00:13:39,760 --> 00:13:39,770 intermolecular forces now 525 00:13:39,770 --> 00:13:51,860 intermolecular forces now let's we have simply in in in in in a 526 00:13:51,860 --> 00:13:51,870 let's we have simply in in in in in a 527 00:13:51,870 --> 00:13:54,290 let's we have simply in in in in in a solid or liquid and a substance actually 528 00:13:54,290 --> 00:13:54,300 solid or liquid and a substance actually 529 00:13:54,300 --> 00:13:56,770 solid or liquid and a substance actually we can talk about two kinds of 530 00:13:56,770 --> 00:13:56,780 we can talk about two kinds of 531 00:13:56,780 --> 00:13:59,710 we can talk about two kinds of attraction forces one is called the 532 00:13:59,710 --> 00:13:59,720 attraction forces one is called the 533 00:13:59,720 --> 00:14:04,610 attraction forces one is called the intra molecular attraction forces the 534 00:14:04,610 --> 00:14:04,620 intra molecular attraction forces the 535 00:14:04,620 --> 00:14:07,250 intra molecular attraction forces the other one is called inter molecular 536 00:14:07,250 --> 00:14:07,260 other one is called inter molecular 537 00:14:07,260 --> 00:14:10,820 other one is called inter molecular attraction forces now intra molecular 538 00:14:10,820 --> 00:14:10,830 attraction forces now intra molecular 539 00:14:10,830 --> 00:14:12,410 attraction forces now intra molecular attraction forces is actually the 540 00:14:12,410 --> 00:14:12,420 attraction forces is actually the 541 00:14:12,420 --> 00:14:17,120 attraction forces is actually the chemical bonds right and intermolecular 542 00:14:17,120 --> 00:14:17,130 chemical bonds right and intermolecular 543 00:14:17,130 --> 00:14:20,600 chemical bonds right and intermolecular attractions are the forces that we have 544 00:14:20,600 --> 00:14:20,610 attractions are the forces that we have 545 00:14:20,610 --> 00:14:23,960 attractions are the forces that we have talked about to explain the properties 546 00:14:23,960 --> 00:14:23,970 talked about to explain the properties 547 00:14:23,970 --> 00:14:27,050 talked about to explain the properties of solid liquid and gases right the 548 00:14:27,050 --> 00:14:27,060 of solid liquid and gases right the 549 00:14:27,060 --> 00:14:30,130 of solid liquid and gases right the gases and we should also know that the 550 00:14:30,130 --> 00:14:30,140 gases and we should also know that the 551 00:14:30,140 --> 00:14:32,450 gases and we should also know that the intermolecular attractions that means 552 00:14:32,450 --> 00:14:32,460 intermolecular attractions that means 553 00:14:32,460 --> 00:14:35,720 intermolecular attractions that means between the molecules is much weaker 554 00:14:35,720 --> 00:14:35,730 between the molecules is much weaker 555 00:14:35,730 --> 00:14:38,630 between the molecules is much weaker than the intra molecular attraction 556 00:14:38,630 --> 00:14:38,640 than the intra molecular attraction 557 00:14:38,640 --> 00:14:41,570 than the intra molecular attraction which is a chemical bond so the chemical 558 00:14:41,570 --> 00:14:41,580 which is a chemical bond so the chemical 559 00:14:41,580 --> 00:14:44,180 which is a chemical bond so the chemical bond is also an attraction but it is 560 00:14:44,180 --> 00:14:44,190 bond is also an attraction but it is 561 00:14:44,190 --> 00:14:46,130 bond is also an attraction but it is much much stronger than the 562 00:14:46,130 --> 00:14:46,140 much much stronger than the 563 00:14:46,140 --> 00:14:47,630 much much stronger than the intermolecular attraction this is what 564 00:14:47,630 --> 00:14:47,640 intermolecular attraction this is what 565 00:14:47,640 --> 00:14:49,700 intermolecular attraction this is what it simply shows that here we have a 566 00:14:49,700 --> 00:14:49,710 it simply shows that here we have a 567 00:14:49,710 --> 00:14:51,380 it simply shows that here we have a chemical bond and that's an attraction 568 00:14:51,380 --> 00:14:51,390 chemical bond and that's an attraction 569 00:14:51,390 --> 00:14:54,230 chemical bond and that's an attraction also but here we have the attraction 570 00:14:54,230 --> 00:14:54,240 also but here we have the attraction 571 00:14:54,240 --> 00:14:55,870 also but here we have the attraction between two molecules this is an 572 00:14:55,870 --> 00:14:55,880 between two molecules this is an 573 00:14:55,880 --> 00:14:59,060 between two molecules this is an intermolecular and this is an intra 574 00:14:59,060 --> 00:14:59,070 intermolecular and this is an intra 575 00:14:59,070 --> 00:15:03,650 intermolecular and this is an intra molecular attraction intra inter so we 576 00:15:03,650 --> 00:15:03,660 molecular attraction intra inter so we 577 00:15:03,660 --> 00:15:08,350 molecular attraction intra inter so we should simply remember those again and 578 00:15:08,350 --> 00:15:08,360 579 00:15:08,360 --> 00:15:11,600 many physical properties that reflects 580 00:15:11,600 --> 00:15:11,610 many physical properties that reflects 581 00:15:11,610 --> 00:15:13,790 many physical properties that reflects intermolecular forces like boiling 582 00:15:13,790 --> 00:15:13,800 intermolecular forces like boiling 583 00:15:13,800 --> 00:15:16,910 intermolecular forces like boiling points Mountain points viscosity surface 584 00:15:16,910 --> 00:15:16,920 points Mountain points viscosity surface 585 00:15:16,920 --> 00:15:20,270 points Mountain points viscosity surface tension and capillary actions all of 586 00:15:20,270 --> 00:15:20,280 tension and capillary actions all of 587 00:15:20,280 --> 00:15:22,820 tension and capillary actions all of these properties which are simply 588 00:15:22,820 --> 00:15:22,830 these properties which are simply 589 00:15:22,830 --> 00:15:25,250 these properties which are simply considered as physical properties can be 590 00:15:25,250 --> 00:15:25,260 considered as physical properties can be 591 00:15:25,260 --> 00:15:28,100 considered as physical properties can be explained or can be compared by 592 00:15:28,100 --> 00:15:28,110 explained or can be compared by 593 00:15:28,110 --> 00:15:31,550 explained or can be compared by comparing the intermolecular attractions 594 00:15:31,550 --> 00:15:31,560 comparing the intermolecular attractions 595 00:15:31,560 --> 00:15:38,720 comparing the intermolecular attractions intermolecular - intermolecular forces 596 00:15:38,720 --> 00:15:38,730 597 00:15:38,730 --> 00:15:42,960 okay types of intermolecular forces we 598 00:15:42,960 --> 00:15:42,970 okay types of intermolecular forces we 599 00:15:42,970 --> 00:15:46,220 okay types of intermolecular forces we simply classify them as follow 600 00:15:46,220 --> 00:15:46,230 simply classify them as follow 601 00:15:46,230 --> 00:15:49,980 simply classify them as follow dispersion forces this is the one first 602 00:15:49,980 --> 00:15:49,990 dispersion forces this is the one first 603 00:15:49,990 --> 00:15:52,379 dispersion forces this is the one first one and it's sometimes called London 604 00:15:52,379 --> 00:15:52,389 one and it's sometimes called London 605 00:15:52,389 --> 00:15:55,819 one and it's sometimes called London dispersion forces dipole-dipole forces 606 00:15:55,819 --> 00:15:55,829 dispersion forces dipole-dipole forces 607 00:15:55,829 --> 00:15:58,170 dispersion forces dipole-dipole forces hydrogen bonding it's a special type of 608 00:15:58,170 --> 00:15:58,180 hydrogen bonding it's a special type of 609 00:15:58,180 --> 00:16:01,410 hydrogen bonding it's a special type of dipole-dipole forces ion dipole forces 610 00:16:01,410 --> 00:16:01,420 dipole-dipole forces ion dipole forces 611 00:16:01,420 --> 00:16:04,619 dipole-dipole forces ion dipole forces this is actually appears only in liquids 612 00:16:04,619 --> 00:16:04,629 this is actually appears only in liquids 613 00:16:04,629 --> 00:16:08,790 this is actually appears only in liquids in solutions like this and here says the 614 00:16:08,790 --> 00:16:08,800 in solutions like this and here says the 615 00:16:08,800 --> 00:16:10,920 in solutions like this and here says the first two types are also referred to 616 00:16:10,920 --> 00:16:10,930 first two types are also referred to 617 00:16:10,930 --> 00:16:13,829 first two types are also referred to collectively as van der Waals forces so 618 00:16:13,829 --> 00:16:13,839 collectively as van der Waals forces so 619 00:16:13,839 --> 00:16:16,379 collectively as van der Waals forces so when we talk about Venerable forces we 620 00:16:16,379 --> 00:16:16,389 when we talk about Venerable forces we 621 00:16:16,389 --> 00:16:18,660 when we talk about Venerable forces we mean dispersion forces and dipole-dipole 622 00:16:18,660 --> 00:16:18,670 mean dispersion forces and dipole-dipole 623 00:16:18,670 --> 00:16:21,780 mean dispersion forces and dipole-dipole forces not the hydrogen bonds again now 624 00:16:21,780 --> 00:16:21,790 forces not the hydrogen bonds again now 625 00:16:21,790 --> 00:16:27,840 forces not the hydrogen bonds again now let's try to compare these and explain 626 00:16:27,840 --> 00:16:27,850 let's try to compare these and explain 627 00:16:27,850 --> 00:16:30,239 let's try to compare these and explain what these forces are now dispersion 628 00:16:30,239 --> 00:16:30,249 what these forces are now dispersion 629 00:16:30,249 --> 00:16:35,579 what these forces are now dispersion forces it says here we see that usually 630 00:16:35,579 --> 00:16:35,589 forces it says here we see that usually 631 00:16:35,589 --> 00:16:40,879 forces it says here we see that usually actually dispersion forces are present 632 00:16:40,879 --> 00:16:40,889 actually dispersion forces are present 633 00:16:40,889 --> 00:16:45,749 actually dispersion forces are present in all substances as an intermolecular 634 00:16:45,749 --> 00:16:45,759 in all substances as an intermolecular 635 00:16:45,759 --> 00:16:48,569 in all substances as an intermolecular force as a matter of fact and but it 636 00:16:48,569 --> 00:16:48,579 force as a matter of fact and but it 637 00:16:48,579 --> 00:16:51,929 force as a matter of fact and but it becomes the main intermolecular force if 638 00:16:51,929 --> 00:16:51,939 becomes the main intermolecular force if 639 00:16:51,939 --> 00:16:55,199 becomes the main intermolecular force if you have a non-polar molecule nonpolar 640 00:16:55,199 --> 00:16:55,209 you have a non-polar molecule nonpolar 641 00:16:55,209 --> 00:17:00,269 you have a non-polar molecule nonpolar molecule as a matter of fact now well 642 00:17:00,269 --> 00:17:00,279 molecule as a matter of fact now well 643 00:17:00,279 --> 00:17:04,590 molecule as a matter of fact now well how can we explain that let me just try 644 00:17:04,590 --> 00:17:04,600 how can we explain that let me just try 645 00:17:04,600 --> 00:17:07,889 how can we explain that let me just try to show you how the dispersion forces 646 00:17:07,889 --> 00:17:07,899 to show you how the dispersion forces 647 00:17:07,899 --> 00:17:11,460 to show you how the dispersion forces are explained now 648 00:17:11,460 --> 00:17:11,470 are explained now 649 00:17:11,470 --> 00:17:18,829 are explained now consider for example neon gas right now 650 00:17:18,829 --> 00:17:18,839 consider for example neon gas right now 651 00:17:18,839 --> 00:17:24,120 consider for example neon gas right now neon gas is more atomic noble gas it is 652 00:17:24,120 --> 00:17:24,130 neon gas is more atomic noble gas it is 653 00:17:24,130 --> 00:17:26,039 neon gas is more atomic noble gas it is gas at room temperature but if you lower 654 00:17:26,039 --> 00:17:26,049 gas at room temperature but if you lower 655 00:17:26,049 --> 00:17:29,610 gas at room temperature but if you lower the temperature they will be liquefied 656 00:17:29,610 --> 00:17:29,620 the temperature they will be liquefied 657 00:17:29,620 --> 00:17:31,950 the temperature they will be liquefied you can have a liquid neon as a matter 658 00:17:31,950 --> 00:17:31,960 you can have a liquid neon as a matter 659 00:17:31,960 --> 00:17:36,240 you can have a liquid neon as a matter of fact now that means that there is any 660 00:17:36,240 --> 00:17:36,250 of fact now that means that there is any 661 00:17:36,250 --> 00:17:39,590 of fact now that means that there is any traction forces between neon molecules 662 00:17:39,590 --> 00:17:39,600 traction forces between neon molecules 663 00:17:39,600 --> 00:17:43,769 traction forces between neon molecules now what is the source of its attraction 664 00:17:43,769 --> 00:17:43,779 now what is the source of its attraction 665 00:17:43,779 --> 00:17:45,180 now what is the source of its attraction the source of attraction between two 666 00:17:45,180 --> 00:17:45,190 the source of attraction between two 667 00:17:45,190 --> 00:17:48,810 the source of attraction between two neon neon atoms actually is the 668 00:17:48,810 --> 00:17:48,820 neon neon atoms actually is the 669 00:17:48,820 --> 00:17:51,120 neon neon atoms actually is the the dispersion forces dispersion forces 670 00:17:51,120 --> 00:17:51,130 the dispersion forces dispersion forces 671 00:17:51,130 --> 00:17:54,269 the dispersion forces dispersion forces and it is again as followed this neon 672 00:17:54,269 --> 00:17:54,279 and it is again as followed this neon 673 00:17:54,279 --> 00:17:57,180 and it is again as followed this neon has ten electrons right ten electrons 674 00:17:57,180 --> 00:17:57,190 has ten electrons right ten electrons 675 00:17:57,190 --> 00:18:00,600 has ten electrons right ten electrons let's say how this is the simply the 676 00:18:00,600 --> 00:18:00,610 let's say how this is the simply the 677 00:18:00,610 --> 00:18:05,009 let's say how this is the simply the nucleus and we have the neon atom like 678 00:18:05,009 --> 00:18:05,019 nucleus and we have the neon atom like 679 00:18:05,019 --> 00:18:08,009 nucleus and we have the neon atom like this and this is one neon atom and then 680 00:18:08,009 --> 00:18:08,019 this and this is one neon atom and then 681 00:18:08,019 --> 00:18:10,350 this and this is one neon atom and then I have the other neon atom here like 682 00:18:10,350 --> 00:18:10,360 I have the other neon atom here like 683 00:18:10,360 --> 00:18:11,340 I have the other neon atom here like this 684 00:18:11,340 --> 00:18:11,350 this 685 00:18:11,350 --> 00:18:17,310 this the gases form right same size now 10 686 00:18:17,310 --> 00:18:17,320 the gases form right same size now 10 687 00:18:17,320 --> 00:18:20,690 the gases form right same size now 10 electrons are distributed put in 688 00:18:20,690 --> 00:18:20,700 electrons are distributed put in 689 00:18:20,700 --> 00:18:25,259 electrons are distributed put in orbitals but they move in the neon atom 690 00:18:25,259 --> 00:18:25,269 orbitals but they move in the neon atom 691 00:18:25,269 --> 00:18:30,149 orbitals but they move in the neon atom now suppose that in one instance in a 692 00:18:30,149 --> 00:18:30,159 now suppose that in one instance in a 693 00:18:30,159 --> 00:18:34,649 now suppose that in one instance in a very short time the electrons of neon 694 00:18:34,649 --> 00:18:34,659 very short time the electrons of neon 695 00:18:34,659 --> 00:18:40,730 very short time the electrons of neon are more on this side than on that side 696 00:18:40,730 --> 00:18:40,740 are more on this side than on that side 697 00:18:40,740 --> 00:18:43,249 are more on this side than on that side what happens if you have this 698 00:18:43,249 --> 00:18:43,259 what happens if you have this 699 00:18:43,259 --> 00:18:45,240 what happens if you have this unsymmetrical distributions of the 700 00:18:45,240 --> 00:18:45,250 unsymmetrical distributions of the 701 00:18:45,250 --> 00:18:48,139 unsymmetrical distributions of the electrons in the neon one side more 702 00:18:48,139 --> 00:18:48,149 electrons in the neon one side more 703 00:18:48,149 --> 00:18:51,029 electrons in the neon one side more negative the other side will be more 704 00:18:51,029 --> 00:18:51,039 negative the other side will be more 705 00:18:51,039 --> 00:18:54,210 negative the other side will be more positive that means that the neon atom 706 00:18:54,210 --> 00:18:54,220 positive that means that the neon atom 707 00:18:54,220 --> 00:18:58,499 positive that means that the neon atom will behave as a dipole one side will be 708 00:18:58,499 --> 00:18:58,509 will behave as a dipole one side will be 709 00:18:58,509 --> 00:19:00,779 will behave as a dipole one side will be a little bit negative and this side will 710 00:19:00,779 --> 00:19:00,789 a little bit negative and this side will 711 00:19:00,789 --> 00:19:03,149 a little bit negative and this side will be a little bit positive again right 712 00:19:03,149 --> 00:19:03,159 be a little bit positive again right 713 00:19:03,159 --> 00:19:07,769 be a little bit positive again right very short time now but when you have 714 00:19:07,769 --> 00:19:07,779 very short time now but when you have 715 00:19:07,779 --> 00:19:10,560 very short time now but when you have this polarization this is called the 716 00:19:10,560 --> 00:19:10,570 this polarization this is called the 717 00:19:10,570 --> 00:19:12,509 this polarization this is called the polarization of the neon that means more 718 00:19:12,509 --> 00:19:12,519 polarization of the neon that means more 719 00:19:12,519 --> 00:19:15,810 polarization of the neon that means more electrons there and less there then the 720 00:19:15,810 --> 00:19:15,820 electrons there and less there then the 721 00:19:15,820 --> 00:19:19,769 electrons there and less there then the neon atom which is next to this one will 722 00:19:19,769 --> 00:19:19,779 neon atom which is next to this one will 723 00:19:19,779 --> 00:19:24,149 neon atom which is next to this one will also be affected by this and as soon as 724 00:19:24,149 --> 00:19:24,159 also be affected by this and as soon as 725 00:19:24,159 --> 00:19:27,600 also be affected by this and as soon as that happens here I will have simply 726 00:19:27,600 --> 00:19:27,610 that happens here I will have simply 727 00:19:27,610 --> 00:19:30,149 that happens here I will have simply more electrons on this side and less 728 00:19:30,149 --> 00:19:30,159 more electrons on this side and less 729 00:19:30,159 --> 00:19:32,279 more electrons on this side and less electron on that side this side of this 730 00:19:32,279 --> 00:19:32,289 electron on that side this side of this 731 00:19:32,289 --> 00:19:35,009 electron on that side this side of this neon will be Delta minus this side will 732 00:19:35,009 --> 00:19:35,019 neon will be Delta minus this side will 733 00:19:35,019 --> 00:19:36,990 neon will be Delta minus this side will be Delta plus now there's going to be 734 00:19:36,990 --> 00:19:37,000 be Delta plus now there's going to be 735 00:19:37,000 --> 00:19:39,930 be Delta plus now there's going to be another neon atom here actually and the 736 00:19:39,930 --> 00:19:39,940 another neon atom here actually and the 737 00:19:39,940 --> 00:19:42,299 another neon atom here actually and the same things will happen there and so on 738 00:19:42,299 --> 00:19:42,309 same things will happen there and so on 739 00:19:42,309 --> 00:19:44,850 same things will happen there and so on so what will happen in an instant time 740 00:19:44,850 --> 00:19:44,860 so what will happen in an instant time 741 00:19:44,860 --> 00:19:47,519 so what will happen in an instant time very short time here I have the neon 742 00:19:47,519 --> 00:19:47,529 very short time here I have the neon 743 00:19:47,529 --> 00:19:50,430 very short time here I have the neon atom one sign is a little bit negative 744 00:19:50,430 --> 00:19:50,440 atom one sign is a little bit negative 745 00:19:50,440 --> 00:19:52,529 atom one sign is a little bit negative due to the unsymmetrical distributions 746 00:19:52,529 --> 00:19:52,539 due to the unsymmetrical distributions 747 00:19:52,539 --> 00:19:54,629 due to the unsymmetrical distributions of the electrons on homogeneous so you 748 00:19:54,629 --> 00:19:54,639 of the electrons on homogeneous so you 749 00:19:54,639 --> 00:19:56,519 of the electrons on homogeneous so you can call it one side a little positive 750 00:19:56,519 --> 00:19:56,529 can call it one side a little positive 751 00:19:56,529 --> 00:19:58,320 can call it one side a little positive now this one is affected by that this 752 00:19:58,320 --> 00:19:58,330 now this one is affected by that this 753 00:19:58,330 --> 00:20:00,869 now this one is affected by that this atom also this side negative this side 754 00:20:00,869 --> 00:20:00,879 atom also this side negative this side 755 00:20:00,879 --> 00:20:02,670 atom also this side negative this side positive this side becomes 756 00:20:02,670 --> 00:20:02,680 positive this side becomes 757 00:20:02,680 --> 00:20:04,350 positive this side becomes again negative positive negative 758 00:20:04,350 --> 00:20:04,360 again negative positive negative 759 00:20:04,360 --> 00:20:08,250 again negative positive negative positive what happens it becomes like 760 00:20:08,250 --> 00:20:08,260 positive what happens it becomes like 761 00:20:08,260 --> 00:20:11,250 positive what happens it becomes like dipole dipole dipole attractions right 762 00:20:11,250 --> 00:20:11,260 dipole dipole dipole attractions right 763 00:20:11,260 --> 00:20:14,090 dipole dipole dipole attractions right dipole-dipole attraction this creates 764 00:20:14,090 --> 00:20:14,100 dipole-dipole attraction this creates 765 00:20:14,100 --> 00:20:18,120 dipole-dipole attraction this creates the attraction force between the neon 766 00:20:18,120 --> 00:20:18,130 the attraction force between the neon 767 00:20:18,130 --> 00:20:20,640 the attraction force between the neon atoms actually even though the neon 768 00:20:20,640 --> 00:20:20,650 atoms actually even though the neon 769 00:20:20,650 --> 00:20:24,210 atoms actually even though the neon molecule atom is not polar right it is a 770 00:20:24,210 --> 00:20:24,220 molecule atom is not polar right it is a 771 00:20:24,220 --> 00:20:27,120 molecule atom is not polar right it is a non-polar atom spherical actually but in 772 00:20:27,120 --> 00:20:27,130 non-polar atom spherical actually but in 773 00:20:27,130 --> 00:20:29,960 non-polar atom spherical actually but in a very short time this happens now an 774 00:20:29,960 --> 00:20:29,970 a very short time this happens now an 775 00:20:29,970 --> 00:20:34,410 a very short time this happens now an instant later then the whole electrons 776 00:20:34,410 --> 00:20:34,420 instant later then the whole electrons 777 00:20:34,420 --> 00:20:37,200 instant later then the whole electrons can move on that side now that side will 778 00:20:37,200 --> 00:20:37,210 can move on that side now that side will 779 00:20:37,210 --> 00:20:38,910 can move on that side now that side will be positive this side will be negative 780 00:20:38,910 --> 00:20:38,920 be positive this side will be negative 781 00:20:38,920 --> 00:20:41,520 be positive this side will be negative positive negative positive but still 782 00:20:41,520 --> 00:20:41,530 positive negative positive but still 783 00:20:41,530 --> 00:20:44,490 positive negative positive but still there's going to be attraction due to 784 00:20:44,490 --> 00:20:44,500 there's going to be attraction due to 785 00:20:44,500 --> 00:20:46,860 there's going to be attraction due to this polarizations or formations of a 786 00:20:46,860 --> 00:20:46,870 this polarizations or formations of a 787 00:20:46,870 --> 00:20:50,310 this polarizations or formations of a dipole actually on the atoms and this 788 00:20:50,310 --> 00:20:50,320 dipole actually on the atoms and this 789 00:20:50,320 --> 00:20:54,690 dipole actually on the atoms and this kind of force or intermolecular forces 790 00:20:54,690 --> 00:20:54,700 kind of force or intermolecular forces 791 00:20:54,700 --> 00:20:57,990 kind of force or intermolecular forces are called London forces dispersion 792 00:20:57,990 --> 00:20:58,000 are called London forces dispersion 793 00:20:58,000 --> 00:21:00,750 are called London forces dispersion forces now the question is in which 794 00:21:00,750 --> 00:21:00,760 forces now the question is in which 795 00:21:00,760 --> 00:21:03,390 forces now the question is in which molecules and which atoms this simply 796 00:21:03,390 --> 00:21:03,400 molecules and which atoms this simply 797 00:21:03,400 --> 00:21:06,240 molecules and which atoms this simply takes place it takes place it is present 798 00:21:06,240 --> 00:21:06,250 takes place it takes place it is present 799 00:21:06,250 --> 00:21:10,680 takes place it takes place it is present in all substances between all molecules 800 00:21:10,680 --> 00:21:10,690 in all substances between all molecules 801 00:21:10,690 --> 00:21:18,830 in all substances between all molecules all right now let me try to ask you this 802 00:21:18,830 --> 00:21:18,840 803 00:21:18,840 --> 00:21:25,620 what is the main factor which will 804 00:21:25,620 --> 00:21:25,630 what is the main factor which will 805 00:21:25,630 --> 00:21:31,560 what is the main factor which will determine this dipole actually 806 00:21:31,560 --> 00:21:31,570 determine this dipole actually 807 00:21:31,570 --> 00:21:34,830 determine this dipole actually attraction that means is this dispersion 808 00:21:34,830 --> 00:21:34,840 attraction that means is this dispersion 809 00:21:34,840 --> 00:21:36,660 attraction that means is this dispersion forces what will be the main factor the 810 00:21:36,660 --> 00:21:36,670 forces what will be the main factor the 811 00:21:36,670 --> 00:21:39,630 forces what will be the main factor the main factor actually will be this how 812 00:21:39,630 --> 00:21:39,640 main factor actually will be this how 813 00:21:39,640 --> 00:21:44,610 main factor actually will be this how easy to move the electron in one atom to 814 00:21:44,610 --> 00:21:44,620 easy to move the electron in one atom to 815 00:21:44,620 --> 00:21:48,000 easy to move the electron in one atom to this fashion that means how easy to 816 00:21:48,000 --> 00:21:48,010 this fashion that means how easy to 817 00:21:48,010 --> 00:21:51,480 this fashion that means how easy to distort the electron distribution in in 818 00:21:51,480 --> 00:21:51,490 distort the electron distribution in in 819 00:21:51,490 --> 00:21:54,750 distort the electron distribution in in a molecule or an atom will determine how 820 00:21:54,750 --> 00:21:54,760 a molecule or an atom will determine how 821 00:21:54,760 --> 00:21:58,560 a molecule or an atom will determine how strong will be the dispersion forces the 822 00:21:58,560 --> 00:21:58,570 strong will be the dispersion forces the 823 00:21:58,570 --> 00:22:01,770 strong will be the dispersion forces the attraction actually right now if it is 824 00:22:01,770 --> 00:22:01,780 attraction actually right now if it is 825 00:22:01,780 --> 00:22:03,600 attraction actually right now if it is very easy to disturb we call that 826 00:22:03,600 --> 00:22:03,610 very easy to disturb we call that 827 00:22:03,610 --> 00:22:06,660 very easy to disturb we call that polarizations polarize the atom of the 828 00:22:06,660 --> 00:22:06,670 polarizations polarize the atom of the 829 00:22:06,670 --> 00:22:10,170 polarizations polarize the atom of the molecule then the attraction dispersion 830 00:22:10,170 --> 00:22:10,180 molecule then the attraction dispersion 831 00:22:10,180 --> 00:22:12,840 molecule then the attraction dispersion forces will be high if the polarization 832 00:22:12,840 --> 00:22:12,850 forces will be high if the polarization 833 00:22:12,850 --> 00:22:15,390 forces will be high if the polarization is not easy but difficult then the 834 00:22:15,390 --> 00:22:15,400 is not easy but difficult then the 835 00:22:15,400 --> 00:22:16,590 is not easy but difficult then the dispersion forces will 836 00:22:16,590 --> 00:22:16,600 dispersion forces will 837 00:22:16,600 --> 00:22:20,400 dispersion forces will now this polarization will be determined 838 00:22:20,400 --> 00:22:20,410 now this polarization will be determined 839 00:22:20,410 --> 00:22:24,900 now this polarization will be determined by the size of the molecule or the size 840 00:22:24,900 --> 00:22:24,910 by the size of the molecule or the size 841 00:22:24,910 --> 00:22:28,530 by the size of the molecule or the size of the atoms the larger the size of the 842 00:22:28,530 --> 00:22:28,540 of the atoms the larger the size of the 843 00:22:28,540 --> 00:22:31,020 of the atoms the larger the size of the atom and the larger the molecule that 844 00:22:31,020 --> 00:22:31,030 atom and the larger the molecule that 845 00:22:31,030 --> 00:22:34,230 atom and the larger the molecule that means more electron there and it will be 846 00:22:34,230 --> 00:22:34,240 means more electron there and it will be 847 00:22:34,240 --> 00:22:38,010 means more electron there and it will be easy to polarize those kind of molecule 848 00:22:38,010 --> 00:22:38,020 easy to polarize those kind of molecule 849 00:22:38,020 --> 00:22:41,630 easy to polarize those kind of molecule and that will result actually stronger 850 00:22:41,630 --> 00:22:41,640 and that will result actually stronger 851 00:22:41,640 --> 00:22:45,000 and that will result actually stronger dispersion forces between the molecules 852 00:22:45,000 --> 00:22:45,010 dispersion forces between the molecules 853 00:22:45,010 --> 00:22:47,490 dispersion forces between the molecules so let's say remember that this is what 854 00:22:47,490 --> 00:22:47,500 so let's say remember that this is what 855 00:22:47,500 --> 00:22:51,660 so let's say remember that this is what is the dispersion forces actually the 856 00:22:51,660 --> 00:22:51,670 is the dispersion forces actually the 857 00:22:51,670 --> 00:23:00,150 is the dispersion forces actually the dispersion forces now the factors gained 858 00:23:00,150 --> 00:23:00,160 dispersion forces now the factors gained 859 00:23:00,160 --> 00:23:01,920 dispersion forces now the factors gained a fair amount dispersion forces in the 860 00:23:01,920 --> 00:23:01,930 a fair amount dispersion forces in the 861 00:23:01,930 --> 00:23:03,330 a fair amount dispersion forces in the molecule factors which affect the amount 862 00:23:03,330 --> 00:23:03,340 molecule factors which affect the amount 863 00:23:03,340 --> 00:23:09,000 molecule factors which affect the amount and number of electrons in an atom or in 864 00:23:09,000 --> 00:23:09,010 and number of electrons in an atom or in 865 00:23:09,010 --> 00:23:10,890 and number of electrons in an atom or in a molecule doesn't matter the more 866 00:23:10,890 --> 00:23:10,900 a molecule doesn't matter the more 867 00:23:10,900 --> 00:23:13,250 a molecule doesn't matter the more electrons we have that means the more 868 00:23:13,250 --> 00:23:13,260 electrons we have that means the more 869 00:23:13,260 --> 00:23:15,690 electrons we have that means the more stronger will be the dispersion forces 870 00:23:15,690 --> 00:23:15,700 stronger will be the dispersion forces 871 00:23:15,700 --> 00:23:20,010 stronger will be the dispersion forces and size of atom or molecule simply the 872 00:23:20,010 --> 00:23:20,020 and size of atom or molecule simply the 873 00:23:20,020 --> 00:23:22,440 and size of atom or molecule simply the molecular weight again the size shape of 874 00:23:22,440 --> 00:23:22,450 molecular weight again the size shape of 875 00:23:22,450 --> 00:23:24,240 molecular weight again the size shape of molecules with the similar masses or 876 00:23:24,240 --> 00:23:24,250 molecules with the similar masses or 877 00:23:24,250 --> 00:23:27,270 molecules with the similar masses or compact less dispersion actually when 878 00:23:27,270 --> 00:23:27,280 compact less dispersion actually when 879 00:23:27,280 --> 00:23:30,810 compact less dispersion actually when you have the same size of molecule but 880 00:23:30,810 --> 00:23:30,820 you have the same size of molecule but 881 00:23:30,820 --> 00:23:34,290 you have the same size of molecule but different shape of the molecules like in 882 00:23:34,290 --> 00:23:34,300 different shape of the molecules like in 883 00:23:34,300 --> 00:23:40,050 different shape of the molecules like in this case here we have n pentane c5h12 884 00:23:40,050 --> 00:23:40,060 this case here we have n pentane c5h12 885 00:23:40,060 --> 00:23:43,700 this case here we have n pentane c5h12 and then we have no pentane c5h12 both 886 00:23:43,700 --> 00:23:43,710 and then we have no pentane c5h12 both 887 00:23:43,710 --> 00:23:46,560 and then we have no pentane c5h12 both molecule has the same number of carbon 888 00:23:46,560 --> 00:23:46,570 molecule has the same number of carbon 889 00:23:46,570 --> 00:23:48,510 molecule has the same number of carbon and hydrogen atoms same weight same 890 00:23:48,510 --> 00:23:48,520 and hydrogen atoms same weight same 891 00:23:48,520 --> 00:23:50,400 and hydrogen atoms same weight same number of electrons but the shape are 892 00:23:50,400 --> 00:23:50,410 number of electrons but the shape are 893 00:23:50,410 --> 00:23:54,540 number of electrons but the shape are different so one is sort of longer again 894 00:23:54,540 --> 00:23:54,550 different so one is sort of longer again 895 00:23:54,550 --> 00:23:57,480 different so one is sort of longer again and the other one is sort of you know 896 00:23:57,480 --> 00:23:57,490 and the other one is sort of you know 897 00:23:57,490 --> 00:24:00,120 and the other one is sort of you know compact like this which one will be more 898 00:24:00,120 --> 00:24:00,130 compact like this which one will be more 899 00:24:00,130 --> 00:24:03,540 compact like this which one will be more easy to polarize this one will be more 900 00:24:03,540 --> 00:24:03,550 easy to polarize this one will be more 901 00:24:03,550 --> 00:24:06,030 easy to polarize this one will be more easy to polarize right so that simply 902 00:24:06,030 --> 00:24:06,040 easy to polarize right so that simply 903 00:24:06,040 --> 00:24:08,700 easy to polarize right so that simply means that the dispersion forces in 904 00:24:08,700 --> 00:24:08,710 means that the dispersion forces in 905 00:24:08,710 --> 00:24:12,810 means that the dispersion forces in normal pentane will be stronger than the 906 00:24:12,810 --> 00:24:12,820 normal pentane will be stronger than the 907 00:24:12,820 --> 00:24:17,430 normal pentane will be stronger than the dispersion forces in neopentane now how 908 00:24:17,430 --> 00:24:17,440 dispersion forces in neopentane now how 909 00:24:17,440 --> 00:24:22,320 dispersion forces in neopentane now how this reflects this reflects in the 910 00:24:22,320 --> 00:24:22,330 this reflects this reflects in the 911 00:24:22,330 --> 00:24:25,020 this reflects this reflects in the boiling point of these two compounds you 912 00:24:25,020 --> 00:24:25,030 boiling point of these two compounds you 913 00:24:25,030 --> 00:24:27,930 boiling point of these two compounds you see again in this end pentane the 914 00:24:27,930 --> 00:24:27,940 see again in this end pentane the 915 00:24:27,940 --> 00:24:29,379 see again in this end pentane the boiling point is 916 00:24:29,379 --> 00:24:29,389 boiling point is 917 00:24:29,389 --> 00:24:35,159 boiling point is 3:09 right this is 3 or 9.5 Carolyn and 918 00:24:35,159 --> 00:24:35,169 3:09 right this is 3 or 9.5 Carolyn and 919 00:24:35,169 --> 00:24:38,859 3:09 right this is 3 or 9.5 Carolyn and neopentane 2.80 2.7 Calvin that means 920 00:24:38,859 --> 00:24:38,869 neopentane 2.80 2.7 Calvin that means 921 00:24:38,869 --> 00:24:41,769 neopentane 2.80 2.7 Calvin that means that the boiling point of Noah pentane 922 00:24:41,769 --> 00:24:41,779 that the boiling point of Noah pentane 923 00:24:41,779 --> 00:24:45,249 that the boiling point of Noah pentane is much lower than the boiling point of 924 00:24:45,249 --> 00:24:45,259 is much lower than the boiling point of 925 00:24:45,259 --> 00:24:48,369 is much lower than the boiling point of the normal pentane what does that means 926 00:24:48,369 --> 00:24:48,379 the normal pentane what does that means 927 00:24:48,379 --> 00:24:51,850 the normal pentane what does that means that means that the degree of dispersion 928 00:24:51,850 --> 00:24:51,860 that means that the degree of dispersion 929 00:24:51,860 --> 00:24:54,340 that means that the degree of dispersion forces or the strength of dispersion 930 00:24:54,340 --> 00:24:54,350 forces or the strength of dispersion 931 00:24:54,350 --> 00:24:56,499 forces or the strength of dispersion forces between the molecules or the 932 00:24:56,499 --> 00:24:56,509 forces between the molecules or the 933 00:24:56,509 --> 00:25:00,639 forces between the molecules or the atoms affects the boiling point of that 934 00:25:00,639 --> 00:25:00,649 atoms affects the boiling point of that 935 00:25:00,649 --> 00:25:02,710 atoms affects the boiling point of that compound and actually affects the other 936 00:25:02,710 --> 00:25:02,720 compound and actually affects the other 937 00:25:02,720 --> 00:25:04,629 compound and actually affects the other properties as we will see viscosity 938 00:25:04,629 --> 00:25:04,639 properties as we will see viscosity 939 00:25:04,639 --> 00:25:10,180 properties as we will see viscosity surface tension and so on now this is 940 00:25:10,180 --> 00:25:10,190 surface tension and so on now this is 941 00:25:10,190 --> 00:25:12,609 surface tension and so on now this is again the polarizability and the boiling 942 00:25:12,609 --> 00:25:12,619 again the polarizability and the boiling 943 00:25:12,619 --> 00:25:17,649 again the polarizability and the boiling point what we simply compare here neon 944 00:25:17,649 --> 00:25:17,659 point what we simply compare here neon 945 00:25:17,659 --> 00:25:21,789 point what we simply compare here neon argon Krypton xenon now all of these are 946 00:25:21,789 --> 00:25:21,799 argon Krypton xenon now all of these are 947 00:25:21,799 --> 00:25:24,879 argon Krypton xenon now all of these are atomic actually and they are not polar 948 00:25:24,879 --> 00:25:24,889 atomic actually and they are not polar 949 00:25:24,889 --> 00:25:27,879 atomic actually and they are not polar and also fluorine molecule chlorine 950 00:25:27,879 --> 00:25:27,889 and also fluorine molecule chlorine 951 00:25:27,889 --> 00:25:29,799 and also fluorine molecule chlorine molecule bromine and iodine again they 952 00:25:29,799 --> 00:25:29,809 molecule bromine and iodine again they 953 00:25:29,809 --> 00:25:32,320 molecule bromine and iodine again they are nonpolar molecule so the only 954 00:25:32,320 --> 00:25:32,330 are nonpolar molecule so the only 955 00:25:32,330 --> 00:25:35,680 are nonpolar molecule so the only attraction forces between two nonpolar 956 00:25:35,680 --> 00:25:35,690 attraction forces between two nonpolar 957 00:25:35,690 --> 00:25:38,440 attraction forces between two nonpolar molecules is the dispersion forces 958 00:25:38,440 --> 00:25:38,450 molecules is the dispersion forces 959 00:25:38,450 --> 00:25:40,450 molecules is the dispersion forces nothing else but the dispersion forces 960 00:25:40,450 --> 00:25:40,460 nothing else but the dispersion forces 961 00:25:40,460 --> 00:25:44,349 nothing else but the dispersion forces so as we see here that the mountain 962 00:25:44,349 --> 00:25:44,359 so as we see here that the mountain 963 00:25:44,359 --> 00:25:47,289 so as we see here that the mountain point of the substances for example 964 00:25:47,289 --> 00:25:47,299 point of the substances for example 965 00:25:47,299 --> 00:25:50,080 point of the substances for example going from neon to argon Krypton and 966 00:25:50,080 --> 00:25:50,090 going from neon to argon Krypton and 967 00:25:50,090 --> 00:25:53,560 going from neon to argon Krypton and xenon increases an increase in melting 968 00:25:53,560 --> 00:25:53,570 xenon increases an increase in melting 969 00:25:53,570 --> 00:25:56,220 xenon increases an increase in melting point simply means that increase in the 970 00:25:56,220 --> 00:25:56,230 point simply means that increase in the 971 00:25:56,230 --> 00:26:00,580 point simply means that increase in the inter atomic attraction dispersion 972 00:26:00,580 --> 00:26:00,590 inter atomic attraction dispersion 973 00:26:00,590 --> 00:26:02,590 inter atomic attraction dispersion forces increases dispersion forces and 974 00:26:02,590 --> 00:26:02,600 forces increases dispersion forces and 975 00:26:02,600 --> 00:26:05,889 forces increases dispersion forces and again you see the polarizability will 976 00:26:05,889 --> 00:26:05,899 again you see the polarizability will 977 00:26:05,899 --> 00:26:09,669 again you see the polarizability will increase this way it would be easy to 978 00:26:09,669 --> 00:26:09,679 increase this way it would be easy to 979 00:26:09,679 --> 00:26:13,720 increase this way it would be easy to polarize large xenon atom or large 980 00:26:13,720 --> 00:26:13,730 polarize large xenon atom or large 981 00:26:13,730 --> 00:26:17,139 polarize large xenon atom or large iodine molecule compared to small neon 982 00:26:17,139 --> 00:26:17,149 iodine molecule compared to small neon 983 00:26:17,149 --> 00:26:20,769 iodine molecule compared to small neon atom or fluorine molecule very difficult 984 00:26:20,769 --> 00:26:20,779 atom or fluorine molecule very difficult 985 00:26:20,779 --> 00:26:22,779 atom or fluorine molecule very difficult to polarize the fluorine it's very small 986 00:26:22,779 --> 00:26:22,789 to polarize the fluorine it's very small 987 00:26:22,789 --> 00:26:24,849 to polarize the fluorine it's very small you know number of electrons 18 988 00:26:24,849 --> 00:26:24,859 you know number of electrons 18 989 00:26:24,859 --> 00:26:27,519 you know number of electrons 18 electrons very compact but when you have 990 00:26:27,519 --> 00:26:27,529 electrons very compact but when you have 991 00:26:27,529 --> 00:26:30,820 electrons very compact but when you have iodine a very large nonpolar 992 00:26:30,820 --> 00:26:30,830 iodine a very large nonpolar 993 00:26:30,830 --> 00:26:33,489 iodine a very large nonpolar lot of electrons so much easy to 994 00:26:33,489 --> 00:26:33,499 lot of electrons so much easy to 995 00:26:33,499 --> 00:26:36,039 lot of electrons so much easy to polarize the iodine therefore the 996 00:26:36,039 --> 00:26:36,049 polarize the iodine therefore the 997 00:26:36,049 --> 00:26:38,499 polarize the iodine therefore the dispersion forces in iodine is much much 998 00:26:38,499 --> 00:26:38,509 dispersion forces in iodine is much much 999 00:26:38,509 --> 00:26:40,749 dispersion forces in iodine is much much stronger than the dispersion force and 1000 00:26:40,749 --> 00:26:40,759 stronger than the dispersion force and 1001 00:26:40,759 --> 00:26:42,740 stronger than the dispersion force and fluorine molecule that 1002 00:26:42,740 --> 00:26:42,750 fluorine molecule that 1003 00:26:42,750 --> 00:26:44,690 fluorine molecule that for the boiling point of the iodine is 1004 00:26:44,690 --> 00:26:44,700 for the boiling point of the iodine is 1005 00:26:44,700 --> 00:26:46,550 for the boiling point of the iodine is much higher than the boiling point of 1006 00:26:46,550 --> 00:26:46,560 much higher than the boiling point of 1007 00:26:46,560 --> 00:26:49,220 much higher than the boiling point of the fluorine you see again how the 1008 00:26:49,220 --> 00:26:49,230 the fluorine you see again how the 1009 00:26:49,230 --> 00:26:51,770 the fluorine you see again how the dispersion forces degree of dispersion 1010 00:26:51,770 --> 00:26:51,780 dispersion forces degree of dispersion 1011 00:26:51,780 --> 00:26:54,560 dispersion forces degree of dispersion forces changes the boiling point or 1012 00:26:54,560 --> 00:26:54,570 forces changes the boiling point or 1013 00:26:54,570 --> 00:27:07,370 forces changes the boiling point or affects the boiling point yes yes 1014 00:27:07,370 --> 00:27:07,380 affects the boiling point yes yes 1015 00:27:07,380 --> 00:27:08,780 affects the boiling point yes yes increase in the temperature will 1016 00:27:08,780 --> 00:27:08,790 increase in the temperature will 1017 00:27:08,790 --> 00:27:11,630 increase in the temperature will certainly affect the intermolecular 1018 00:27:11,630 --> 00:27:11,640 certainly affect the intermolecular 1019 00:27:11,640 --> 00:27:14,920 certainly affect the intermolecular forces because kinetic energy increase 1020 00:27:14,920 --> 00:27:14,930 forces because kinetic energy increase 1021 00:27:14,930 --> 00:27:18,410 forces because kinetic energy increase simply if it close to the intermolecular 1022 00:27:18,410 --> 00:27:18,420 simply if it close to the intermolecular 1023 00:27:18,420 --> 00:27:19,910 simply if it close to the intermolecular forces then the effect of the 1024 00:27:19,910 --> 00:27:19,920 forces then the effect of the 1025 00:27:19,920 --> 00:27:22,100 forces then the effect of the intermolecular forces becomes lower in 1026 00:27:22,100 --> 00:27:22,110 intermolecular forces becomes lower in 1027 00:27:22,110 --> 00:27:23,870 intermolecular forces becomes lower in determining the physical properties it 1028 00:27:23,870 --> 00:27:23,880 determining the physical properties it 1029 00:27:23,880 --> 00:27:26,930 determining the physical properties it does but that would be the same for all 1030 00:27:26,930 --> 00:27:26,940 does but that would be the same for all 1031 00:27:26,940 --> 00:27:33,500 does but that would be the same for all actually now the second type of 1032 00:27:33,500 --> 00:27:33,510 actually now the second type of 1033 00:27:33,510 --> 00:27:36,100 actually now the second type of intermolecular forces is dipole-dipole 1034 00:27:36,100 --> 00:27:36,110 intermolecular forces is dipole-dipole 1035 00:27:36,110 --> 00:27:38,420 intermolecular forces is dipole-dipole interactions and this is only possible 1036 00:27:38,420 --> 00:27:38,430 interactions and this is only possible 1037 00:27:38,430 --> 00:27:41,630 interactions and this is only possible if you have polar molecules right and 1038 00:27:41,630 --> 00:27:41,640 if you have polar molecules right and 1039 00:27:41,640 --> 00:27:45,410 if you have polar molecules right and very simple again right the negative 1040 00:27:45,410 --> 00:27:45,420 very simple again right the negative 1041 00:27:45,420 --> 00:27:48,080 very simple again right the negative side of the polar molecule will be 1042 00:27:48,080 --> 00:27:48,090 side of the polar molecule will be 1043 00:27:48,090 --> 00:27:49,910 side of the polar molecule will be attracted by the positive side of the 1044 00:27:49,910 --> 00:27:49,920 attracted by the positive side of the 1045 00:27:49,920 --> 00:27:51,890 attracted by the positive side of the polar molecule and the molecules 1046 00:27:51,890 --> 00:27:51,900 polar molecule and the molecules 1047 00:27:51,900 --> 00:27:54,020 polar molecule and the molecules particularly for example if you have in 1048 00:27:54,020 --> 00:27:54,030 particularly for example if you have in 1049 00:27:54,030 --> 00:27:54,980 particularly for example if you have in the solid state 1050 00:27:54,980 --> 00:27:54,990 the solid state 1051 00:27:54,990 --> 00:27:56,870 the solid state they will orient themselves in such a 1052 00:27:56,870 --> 00:27:56,880 they will orient themselves in such a 1053 00:27:56,880 --> 00:28:01,360 they will orient themselves in such a way to get maximum attraction between 1054 00:28:01,360 --> 00:28:01,370 way to get maximum attraction between 1055 00:28:01,370 --> 00:28:05,000 way to get maximum attraction between dipoles actually between polar molecules 1056 00:28:05,000 --> 00:28:05,010 dipoles actually between polar molecules 1057 00:28:05,010 --> 00:28:07,550 dipoles actually between polar molecules and in the liquids they will be a little 1058 00:28:07,550 --> 00:28:07,560 and in the liquids they will be a little 1059 00:28:07,560 --> 00:28:11,180 and in the liquids they will be a little bit more chaotic way but still the main 1060 00:28:11,180 --> 00:28:11,190 bit more chaotic way but still the main 1061 00:28:11,190 --> 00:28:14,150 bit more chaotic way but still the main attraction will be simply dipole-dipole 1062 00:28:14,150 --> 00:28:14,160 attraction will be simply dipole-dipole 1063 00:28:14,160 --> 00:28:19,210 attraction will be simply dipole-dipole attraction and this is only possible for 1064 00:28:19,210 --> 00:28:19,220 1065 00:28:19,220 --> 00:28:21,770 dipolar molecules actually we have to 1066 00:28:21,770 --> 00:28:21,780 dipolar molecules actually we have to 1067 00:28:21,780 --> 00:28:23,300 dipolar molecules actually we have to have polar molecules to have 1068 00:28:23,300 --> 00:28:23,310 have polar molecules to have 1069 00:28:23,310 --> 00:28:26,060 have polar molecules to have dipole-dipole interactions to operate in 1070 00:28:26,060 --> 00:28:26,070 dipole-dipole interactions to operate in 1071 00:28:26,070 --> 00:28:31,150 dipole-dipole interactions to operate in that substance 1072 00:28:31,150 --> 00:28:31,160 1073 00:28:31,160 --> 00:28:37,070 now this simply shows how the 1074 00:28:37,070 --> 00:28:37,080 now this simply shows how the 1075 00:28:37,080 --> 00:28:39,800 now this simply shows how the dipole-dipole interactions and the 1076 00:28:39,800 --> 00:28:39,810 dipole-dipole interactions and the 1077 00:28:39,810 --> 00:28:43,990 dipole-dipole interactions and the dipole moment 'strength affects the 1078 00:28:43,990 --> 00:28:44,000 dipole moment 'strength affects the 1079 00:28:44,000 --> 00:28:46,730 dipole moment 'strength affects the properties particularly in this case the 1080 00:28:46,730 --> 00:28:46,740 properties particularly in this case the 1081 00:28:46,740 --> 00:28:49,310 properties particularly in this case the boiling point are given all here you see 1082 00:28:49,310 --> 00:28:49,320 boiling point are given all here you see 1083 00:28:49,320 --> 00:28:52,190 boiling point are given all here you see now these molecules this is propane this 1084 00:28:52,190 --> 00:28:52,200 now these molecules this is propane this 1085 00:28:52,200 --> 00:28:55,520 now these molecules this is propane this is dimethyl ether Isetta aldehyde C the 1086 00:28:55,520 --> 00:28:55,530 is dimethyl ether Isetta aldehyde C the 1087 00:28:55,530 --> 00:28:56,549 is dimethyl ether Isetta aldehyde C the nitrile 1088 00:28:56,549 --> 00:28:56,559 nitrile 1089 00:28:56,559 --> 00:28:59,279 nitrile and all of these are polar molecules 1090 00:28:59,279 --> 00:28:59,289 and all of these are polar molecules 1091 00:28:59,289 --> 00:29:01,649 and all of these are polar molecules they are all polar molecules now they 1092 00:29:01,649 --> 00:29:01,659 they are all polar molecules now they 1093 00:29:01,659 --> 00:29:05,100 they are all polar molecules now they all have this almost same molecular 1094 00:29:05,100 --> 00:29:05,110 all have this almost same molecular 1095 00:29:05,110 --> 00:29:08,970 all have this almost same molecular weight this is 44 46 44 41 that means 1096 00:29:08,970 --> 00:29:08,980 weight this is 44 46 44 41 that means 1097 00:29:08,980 --> 00:29:11,820 weight this is 44 46 44 41 that means that the size of the molecule in other 1098 00:29:11,820 --> 00:29:11,830 that the size of the molecule in other 1099 00:29:11,830 --> 00:29:13,919 that the size of the molecule in other words the number of electrons is about 1100 00:29:13,919 --> 00:29:13,929 words the number of electrons is about 1101 00:29:13,929 --> 00:29:16,289 words the number of electrons is about the same you can think about that way so 1102 00:29:16,289 --> 00:29:16,299 the same you can think about that way so 1103 00:29:16,299 --> 00:29:19,169 the same you can think about that way so that simply means that since the size is 1104 00:29:19,169 --> 00:29:19,179 that simply means that since the size is 1105 00:29:19,179 --> 00:29:20,430 that simply means that since the size is about the same 1106 00:29:20,430 --> 00:29:20,440 about the same 1107 00:29:20,440 --> 00:29:22,590 about the same so the polarizability will be about the 1108 00:29:22,590 --> 00:29:22,600 so the polarizability will be about the 1109 00:29:22,600 --> 00:29:25,259 so the polarizability will be about the same that means that the dispersion 1110 00:29:25,259 --> 00:29:25,269 same that means that the dispersion 1111 00:29:25,269 --> 00:29:28,799 same that means that the dispersion forces for all of them will be more or 1112 00:29:28,799 --> 00:29:28,809 forces for all of them will be more or 1113 00:29:28,809 --> 00:29:33,779 forces for all of them will be more or less the same right so the difference 1114 00:29:33,779 --> 00:29:33,789 less the same right so the difference 1115 00:29:33,789 --> 00:29:37,919 less the same right so the difference again of their boiling points results 1116 00:29:37,919 --> 00:29:37,929 again of their boiling points results 1117 00:29:37,929 --> 00:29:41,850 again of their boiling points results from the different typo 1118 00:29:41,850 --> 00:29:41,860 from the different typo 1119 00:29:41,860 --> 00:29:44,100 from the different typo dipole attractions between the molecules 1120 00:29:44,100 --> 00:29:44,110 dipole attractions between the molecules 1121 00:29:44,110 --> 00:29:46,560 dipole attractions between the molecules and as the dipole moment simply 1122 00:29:46,560 --> 00:29:46,570 and as the dipole moment simply 1123 00:29:46,570 --> 00:29:49,409 and as the dipole moment simply increases the dipole dipole attraction 1124 00:29:49,409 --> 00:29:49,419 increases the dipole dipole attraction 1125 00:29:49,419 --> 00:29:52,080 increases the dipole dipole attraction force actually interaction increases 1126 00:29:52,080 --> 00:29:52,090 force actually interaction increases 1127 00:29:52,090 --> 00:29:55,499 force actually interaction increases here the dipole moment point one dipole 1128 00:29:55,499 --> 00:29:55,509 here the dipole moment point one dipole 1129 00:29:55,509 --> 00:29:57,389 here the dipole moment point one dipole moment one three two point seven three 1130 00:29:57,389 --> 00:29:57,399 moment one three two point seven three 1131 00:29:57,399 --> 00:30:01,609 moment one three two point seven three nine you see the boiling point 231 248 1132 00:30:01,609 --> 00:30:01,619 nine you see the boiling point 231 248 1133 00:30:01,619 --> 00:30:05,399 nine you see the boiling point 231 248 234 and 355 you see how the boiling 1134 00:30:05,399 --> 00:30:05,409 234 and 355 you see how the boiling 1135 00:30:05,409 --> 00:30:09,060 234 and 355 you see how the boiling point increases so stronger 1136 00:30:09,060 --> 00:30:09,070 point increases so stronger 1137 00:30:09,070 --> 00:30:11,869 point increases so stronger intermolecular attraction means higher 1138 00:30:11,869 --> 00:30:11,879 intermolecular attraction means higher 1139 00:30:11,879 --> 00:30:14,190 intermolecular attraction means higher boiling points right a higher boiling 1140 00:30:14,190 --> 00:30:14,200 boiling points right a higher boiling 1141 00:30:14,200 --> 00:30:24,659 boiling points right a higher boiling point for the liquids in fact now this 1142 00:30:24,659 --> 00:30:24,669 point for the liquids in fact now this 1143 00:30:24,669 --> 00:30:27,230 point for the liquids in fact now this is in other things now we said we have 1144 00:30:27,230 --> 00:30:27,240 is in other things now we said we have 1145 00:30:27,240 --> 00:30:32,749 is in other things now we said we have three types of intermolecular forces 1146 00:30:32,749 --> 00:30:32,759 three types of intermolecular forces 1147 00:30:32,759 --> 00:30:36,330 three types of intermolecular forces dipole-dipole forces dispersion forces 1148 00:30:36,330 --> 00:30:36,340 dipole-dipole forces dispersion forces 1149 00:30:36,340 --> 00:30:40,499 dipole-dipole forces dispersion forces and hydrogen bond and in solutions we 1150 00:30:40,499 --> 00:30:40,509 and hydrogen bond and in solutions we 1151 00:30:40,509 --> 00:30:43,649 and hydrogen bond and in solutions we have ion dipole forces how can we 1152 00:30:43,649 --> 00:30:43,659 have ion dipole forces how can we 1153 00:30:43,659 --> 00:30:47,249 have ion dipole forces how can we compare these forces in fact which one 1154 00:30:47,249 --> 00:30:47,259 compare these forces in fact which one 1155 00:30:47,259 --> 00:30:51,359 compare these forces in fact which one is dominant which one determines the 1156 00:30:51,359 --> 00:30:51,369 is dominant which one determines the 1157 00:30:51,369 --> 00:30:53,159 is dominant which one determines the physical property all has the highest 1158 00:30:53,159 --> 00:30:53,169 physical property all has the highest 1159 00:30:53,169 --> 00:30:55,919 physical property all has the highest effect on the physical properties let's 1160 00:30:55,919 --> 00:30:55,929 effect on the physical properties let's 1161 00:30:55,929 --> 00:30:58,700 effect on the physical properties let's look at here if two molecules says are 1162 00:30:58,700 --> 00:30:58,710 look at here if two molecules says are 1163 00:30:58,710 --> 00:31:01,350 look at here if two molecules says are comparable size and shape and 1164 00:31:01,350 --> 00:31:01,360 comparable size and shape and 1165 00:31:01,360 --> 00:31:03,629 comparable size and shape and dipole-dipole interactions will likely 1166 00:31:03,629 --> 00:31:03,639 dipole-dipole interactions will likely 1167 00:31:03,639 --> 00:31:07,169 dipole-dipole interactions will likely to be dominating force that means if we 1168 00:31:07,169 --> 00:31:07,179 to be dominating force that means if we 1169 00:31:07,179 --> 00:31:09,690 to be dominating force that means if we have the polar molecules which have 1170 00:31:09,690 --> 00:31:09,700 have the polar molecules which have 1171 00:31:09,700 --> 00:31:10,470 have the polar molecules which have about the 1172 00:31:10,470 --> 00:31:10,480 about the 1173 00:31:10,480 --> 00:31:13,470 about the same molecular weight the same size so 1174 00:31:13,470 --> 00:31:13,480 same molecular weight the same size so 1175 00:31:13,480 --> 00:31:17,159 same molecular weight the same size so the dipole-dipole interactions will 1176 00:31:17,159 --> 00:31:17,169 the dipole-dipole interactions will 1177 00:31:17,169 --> 00:31:18,539 the dipole-dipole interactions will determine the boiling point which is in 1178 00:31:18,539 --> 00:31:18,549 determine the boiling point which is in 1179 00:31:18,549 --> 00:31:20,400 determine the boiling point which is in the previous cases remember as the 1180 00:31:20,400 --> 00:31:20,410 the previous cases remember as the 1181 00:31:20,410 --> 00:31:22,049 the previous cases remember as the dipole moment increased the boiling 1182 00:31:22,049 --> 00:31:22,059 dipole moment increased the boiling 1183 00:31:22,059 --> 00:31:23,669 dipole moment increased the boiling point increase that means that the 1184 00:31:23,669 --> 00:31:23,679 point increase that means that the 1185 00:31:23,679 --> 00:31:26,610 point increase that means that the dipole-dipole attractions increases with 1186 00:31:26,610 --> 00:31:26,620 dipole-dipole attractions increases with 1187 00:31:26,620 --> 00:31:28,560 dipole-dipole attractions increases with the increase in dipole moment of the 1188 00:31:28,560 --> 00:31:28,570 the increase in dipole moment of the 1189 00:31:28,570 --> 00:31:31,860 the increase in dipole moment of the molecule if one molecule is much larger 1190 00:31:31,860 --> 00:31:31,870 molecule if one molecule is much larger 1191 00:31:31,870 --> 00:31:33,900 molecule if one molecule is much larger than the other dispersion forces will 1192 00:31:33,900 --> 00:31:33,910 than the other dispersion forces will 1193 00:31:33,910 --> 00:31:36,090 than the other dispersion forces will likely determine its physical properties 1194 00:31:36,090 --> 00:31:36,100 likely determine its physical properties 1195 00:31:36,100 --> 00:31:39,180 likely determine its physical properties again dispersion forces even though it 1196 00:31:39,180 --> 00:31:39,190 again dispersion forces even though it 1197 00:31:39,190 --> 00:31:43,380 again dispersion forces even though it is present among all molecules but it 1198 00:31:43,380 --> 00:31:43,390 is present among all molecules but it 1199 00:31:43,390 --> 00:31:45,810 is present among all molecules but it becomes more important and more 1200 00:31:45,810 --> 00:31:45,820 becomes more important and more 1201 00:31:45,820 --> 00:31:49,950 becomes more important and more influential when we have large molecules 1202 00:31:49,950 --> 00:31:49,960 influential when we have large molecules 1203 00:31:49,960 --> 00:31:53,549 influential when we have large molecules and a lot of electrons actually so those 1204 00:31:53,549 --> 00:31:53,559 and a lot of electrons actually so those 1205 00:31:53,559 --> 00:31:56,400 and a lot of electrons actually so those large molecules the dispersion forces 1206 00:31:56,400 --> 00:31:56,410 large molecules the dispersion forces 1207 00:31:56,410 --> 00:31:59,549 large molecules the dispersion forces become the dominant intermolecular force 1208 00:31:59,549 --> 00:31:59,559 become the dominant intermolecular force 1209 00:31:59,559 --> 00:32:01,470 become the dominant intermolecular force and that determines a lot of physical 1210 00:32:01,470 --> 00:32:01,480 and that determines a lot of physical 1211 00:32:01,480 --> 00:32:09,860 and that determines a lot of physical properties this is what it simply means 1212 00:32:09,860 --> 00:32:09,870 1213 00:32:09,870 --> 00:32:15,900 now here again we have a graph which 1214 00:32:15,900 --> 00:32:15,910 now here again we have a graph which 1215 00:32:15,910 --> 00:32:18,690 now here again we have a graph which shows the boiling point of certain 1216 00:32:18,690 --> 00:32:18,700 shows the boiling point of certain 1217 00:32:18,700 --> 00:32:21,740 shows the boiling point of certain compounds now these are the hydrides 1218 00:32:21,740 --> 00:32:21,750 compounds now these are the hydrides 1219 00:32:21,750 --> 00:32:25,890 compounds now these are the hydrides this is the simply hydrides 1220 00:32:25,890 --> 00:32:25,900 this is the simply hydrides 1221 00:32:25,900 --> 00:32:29,640 this is the simply hydrides group four right this is group 5 group 6 1222 00:32:29,640 --> 00:32:29,650 group four right this is group 5 group 6 1223 00:32:29,650 --> 00:32:33,870 group four right this is group 5 group 6 and group 7 elements and their compounds 1224 00:32:33,870 --> 00:32:33,880 and group 7 elements and their compounds 1225 00:32:33,880 --> 00:32:36,480 and group 7 elements and their compounds with the hydrogen right and let's start 1226 00:32:36,480 --> 00:32:36,490 with the hydrogen right and let's start 1227 00:32:36,490 --> 00:32:42,900 with the hydrogen right and let's start here we have ch4 methane silane germane 1228 00:32:42,900 --> 00:32:42,910 here we have ch4 methane silane germane 1229 00:32:42,910 --> 00:32:45,630 here we have ch4 methane silane germane and standing right all the same 1230 00:32:45,630 --> 00:32:45,640 and standing right all the same 1231 00:32:45,640 --> 00:32:47,789 and standing right all the same structures what is the difference 1232 00:32:47,789 --> 00:32:47,799 structures what is the difference 1233 00:32:47,799 --> 00:32:50,159 structures what is the difference between them the only difference is the 1234 00:32:50,159 --> 00:32:50,169 between them the only difference is the 1235 00:32:50,169 --> 00:32:52,350 between them the only difference is the molecular weight that means that the 1236 00:32:52,350 --> 00:32:52,360 molecular weight that means that the 1237 00:32:52,360 --> 00:32:55,320 molecular weight that means that the number of electrons actually so what we 1238 00:32:55,320 --> 00:32:55,330 number of electrons actually so what we 1239 00:32:55,330 --> 00:32:58,340 number of electrons actually so what we said as the molecular weight increases 1240 00:32:58,340 --> 00:32:58,350 said as the molecular weight increases 1241 00:32:58,350 --> 00:33:02,220 said as the molecular weight increases the dispersion forces between the 1242 00:33:02,220 --> 00:33:02,230 the dispersion forces between the 1243 00:33:02,230 --> 00:33:06,650 the dispersion forces between the molecule increases so we see that by 1244 00:33:06,650 --> 00:33:06,660 molecule increases so we see that by 1245 00:33:06,660 --> 00:33:09,960 molecule increases so we see that by increasing the boiling point of these 1246 00:33:09,960 --> 00:33:09,970 increasing the boiling point of these 1247 00:33:09,970 --> 00:33:12,240 increasing the boiling point of these compounds for example the boiling point 1248 00:33:12,240 --> 00:33:12,250 compounds for example the boiling point 1249 00:33:12,250 --> 00:33:15,840 compounds for example the boiling point of silane this molecule sh 4 is greater 1250 00:33:15,840 --> 00:33:15,850 of silane this molecule sh 4 is greater 1251 00:33:15,850 --> 00:33:18,120 of silane this molecule sh 4 is greater than the boiling point of methane and 1252 00:33:18,120 --> 00:33:18,130 than the boiling point of methane and 1253 00:33:18,130 --> 00:33:20,280 than the boiling point of methane and germane is greater than that greater 1254 00:33:20,280 --> 00:33:20,290 germane is greater than that greater 1255 00:33:20,290 --> 00:33:24,080 germane is greater than that greater than that that means that dispersion 1256 00:33:24,080 --> 00:33:24,090 than that that means that dispersion 1257 00:33:24,090 --> 00:33:27,409 than that that means that dispersion horses highest in this compound and lows 1258 00:33:27,409 --> 00:33:27,419 horses highest in this compound and lows 1259 00:33:27,419 --> 00:33:29,779 horses highest in this compound and lows lows in this compound and it just 1260 00:33:29,779 --> 00:33:29,789 lows in this compound and it just 1261 00:33:29,789 --> 00:33:32,510 lows in this compound and it just changes with the molecular weight again 1262 00:33:32,510 --> 00:33:32,520 changes with the molecular weight again 1263 00:33:32,520 --> 00:33:34,399 changes with the molecular weight again right this is the molecular weight like 1264 00:33:34,399 --> 00:33:34,409 right this is the molecular weight like 1265 00:33:34,409 --> 00:33:39,100 right this is the molecular weight like this now when you look at the group five 1266 00:33:39,100 --> 00:33:39,110 this now when you look at the group five 1267 00:33:39,110 --> 00:33:44,600 this now when you look at the group five right the simply hydrogen compounds died 1268 00:33:44,600 --> 00:33:44,610 right the simply hydrogen compounds died 1269 00:33:44,610 --> 00:33:48,710 right the simply hydrogen compounds died being here and then we have the ammonia 1270 00:33:48,710 --> 00:33:48,720 being here and then we have the ammonia 1271 00:33:48,720 --> 00:33:52,299 being here and then we have the ammonia molecule here all the others are there 1272 00:33:52,299 --> 00:33:52,309 molecule here all the others are there 1273 00:33:52,309 --> 00:33:58,240 molecule here all the others are there what we see that the boiling point of 1274 00:33:58,240 --> 00:33:58,250 what we see that the boiling point of 1275 00:33:58,250 --> 00:34:01,850 what we see that the boiling point of ammonia is higher than the boiling point 1276 00:34:01,850 --> 00:34:01,860 ammonia is higher than the boiling point 1277 00:34:01,860 --> 00:34:06,139 ammonia is higher than the boiling point of simply the germain right here 1278 00:34:06,139 --> 00:34:06,149 of simply the germain right here 1279 00:34:06,149 --> 00:34:08,270 of simply the germain right here actually what we have here actually this 1280 00:34:08,270 --> 00:34:08,280 actually what we have here actually this 1281 00:34:08,280 --> 00:34:11,419 actually what we have here actually this is the iodine and then this is going to 1282 00:34:11,419 --> 00:34:11,429 is the iodine and then this is going to 1283 00:34:11,429 --> 00:34:13,639 is the iodine and then this is going to be the bromine I guess yes this is going 1284 00:34:13,639 --> 00:34:13,649 be the bromine I guess yes this is going 1285 00:34:13,649 --> 00:34:16,669 be the bromine I guess yes this is going to people mean and the same thing is 1286 00:34:16,669 --> 00:34:16,679 to people mean and the same thing is 1287 00:34:16,679 --> 00:34:20,540 to people mean and the same thing is also true for the HF higher than 1288 00:34:20,540 --> 00:34:20,550 also true for the HF higher than 1289 00:34:20,550 --> 00:34:22,970 also true for the HF higher than expected it should be here actually down 1290 00:34:22,970 --> 00:34:22,980 expected it should be here actually down 1291 00:34:22,980 --> 00:34:24,889 expected it should be here actually down here but it's over there and a water 1292 00:34:24,889 --> 00:34:24,899 here but it's over there and a water 1293 00:34:24,899 --> 00:34:29,050 here but it's over there and a water case also the compounds of the group 1294 00:34:29,050 --> 00:34:29,060 case also the compounds of the group 1295 00:34:29,060 --> 00:34:32,300 case also the compounds of the group simply seven hydrogen compounds delirium 1296 00:34:32,300 --> 00:34:32,310 simply seven hydrogen compounds delirium 1297 00:34:32,310 --> 00:34:38,710 simply seven hydrogen compounds delirium start from there and the water there 1298 00:34:38,710 --> 00:34:38,720 1299 00:34:38,720 --> 00:34:44,800 what is the reason that we have high 1300 00:34:44,800 --> 00:34:44,810 what is the reason that we have high 1301 00:34:44,810 --> 00:34:52,000 what is the reason that we have high boiling points for the water then the 1302 00:34:52,000 --> 00:34:52,010 boiling points for the water then the 1303 00:34:52,010 --> 00:34:55,520 boiling points for the water then the h2s hydrogen sulfide which is the same 1304 00:34:55,520 --> 00:34:55,530 h2s hydrogen sulfide which is the same 1305 00:34:55,530 --> 00:34:59,359 h2s hydrogen sulfide which is the same you know and hydrogen fluoride then the 1306 00:34:59,359 --> 00:34:59,369 you know and hydrogen fluoride then the 1307 00:34:59,369 --> 00:35:07,040 you know and hydrogen fluoride then the hydrogen chloride nh3 actually here and 1308 00:35:07,040 --> 00:35:07,050 hydrogen chloride nh3 actually here and 1309 00:35:07,050 --> 00:35:10,160 hydrogen chloride nh3 actually here and the previous is the phosphine right here 1310 00:35:10,160 --> 00:35:10,170 the previous is the phosphine right here 1311 00:35:10,170 --> 00:35:14,740 the previous is the phosphine right here pH three phosphine and the reason is 1312 00:35:14,740 --> 00:35:14,750 pH three phosphine and the reason is 1313 00:35:14,750 --> 00:35:19,520 pH three phosphine and the reason is there is an extra intermolecular force 1314 00:35:19,520 --> 00:35:19,530 there is an extra intermolecular force 1315 00:35:19,530 --> 00:35:21,530 there is an extra intermolecular force very very strong intermolecular forces 1316 00:35:21,530 --> 00:35:21,540 very very strong intermolecular forces 1317 00:35:21,540 --> 00:35:24,620 very very strong intermolecular forces in these compounds water hydrogen 1318 00:35:24,620 --> 00:35:24,630 in these compounds water hydrogen 1319 00:35:24,630 --> 00:35:27,380 in these compounds water hydrogen fluoride and ammonia that force is 1320 00:35:27,380 --> 00:35:27,390 fluoride and ammonia that force is 1321 00:35:27,390 --> 00:35:41,140 fluoride and ammonia that force is called hydrogen bonding hydrogen bond 1322 00:35:41,140 --> 00:35:41,150 1323 00:35:41,150 --> 00:35:49,150 all right so we have dispersion forces 1324 00:35:49,150 --> 00:35:49,160 1325 00:35:49,160 --> 00:35:52,550 we talked about that second is 1326 00:35:52,550 --> 00:35:52,560 we talked about that second is 1327 00:35:52,560 --> 00:36:01,850 we talked about that second is dipole-dipole now in addition to this 1328 00:36:01,850 --> 00:36:01,860 dipole-dipole now in addition to this 1329 00:36:01,860 --> 00:36:11,510 dipole-dipole now in addition to this now we have three hydrogen bonding now 1330 00:36:11,510 --> 00:36:11,520 now we have three hydrogen bonding now 1331 00:36:11,520 --> 00:36:14,480 now we have three hydrogen bonding now this hydrogen bonding doesn't mean a 1332 00:36:14,480 --> 00:36:14,490 this hydrogen bonding doesn't mean a 1333 00:36:14,490 --> 00:36:18,410 this hydrogen bonding doesn't mean a chemical bond it's just a special name 1334 00:36:18,410 --> 00:36:18,420 chemical bond it's just a special name 1335 00:36:18,420 --> 00:36:20,480 chemical bond it's just a special name for that now let's explain what the 1336 00:36:20,480 --> 00:36:20,490 for that now let's explain what the 1337 00:36:20,490 --> 00:36:25,070 for that now let's explain what the hydrogen bonding is first of all to have 1338 00:36:25,070 --> 00:36:25,080 hydrogen bonding is first of all to have 1339 00:36:25,080 --> 00:36:30,470 hydrogen bonding is first of all to have a hydrogen bonding we must have in the 1340 00:36:30,470 --> 00:36:30,480 a hydrogen bonding we must have in the 1341 00:36:30,480 --> 00:36:34,550 a hydrogen bonding we must have in the molecule a hydrogen atom which is bonded 1342 00:36:34,550 --> 00:36:34,560 molecule a hydrogen atom which is bonded 1343 00:36:34,560 --> 00:36:36,980 molecule a hydrogen atom which is bonded to the most electronegative atoms 1344 00:36:36,980 --> 00:36:36,990 to the most electronegative atoms 1345 00:36:36,990 --> 00:36:38,870 to the most electronegative atoms what are those most electronegative 1346 00:36:38,870 --> 00:36:38,880 what are those most electronegative 1347 00:36:38,880 --> 00:36:40,430 what are those most electronegative atoms tell me what is the most 1348 00:36:40,430 --> 00:36:40,440 atoms tell me what is the most 1349 00:36:40,440 --> 00:36:46,400 atoms tell me what is the most electronegative atom fluorine next one 1350 00:36:46,400 --> 00:36:46,410 electronegative atom fluorine next one 1351 00:36:46,410 --> 00:36:51,500 electronegative atom fluorine next one is oxygen right the next one this is 1352 00:36:51,500 --> 00:36:51,510 is oxygen right the next one this is 1353 00:36:51,510 --> 00:36:56,150 is oxygen right the next one this is four oxygen is simply four three point 1354 00:36:56,150 --> 00:36:56,160 four oxygen is simply four three point 1355 00:36:56,160 --> 00:36:59,750 four oxygen is simply four three point five and then the third one is nitrogen 1356 00:36:59,750 --> 00:36:59,760 five and then the third one is nitrogen 1357 00:36:59,760 --> 00:37:02,980 five and then the third one is nitrogen right these are simply known as the most 1358 00:37:02,980 --> 00:37:02,990 right these are simply known as the most 1359 00:37:02,990 --> 00:37:05,570 right these are simply known as the most electronegative elements most 1360 00:37:05,570 --> 00:37:05,580 electronegative elements most 1361 00:37:05,580 --> 00:37:08,680 electronegative elements most electronegative element now if I have a 1362 00:37:08,680 --> 00:37:08,690 electronegative element now if I have a 1363 00:37:08,690 --> 00:37:11,690 electronegative element now if I have a simply a hydrogen bonded to this most 1364 00:37:11,690 --> 00:37:11,700 simply a hydrogen bonded to this most 1365 00:37:11,700 --> 00:37:15,850 simply a hydrogen bonded to this most electronegative elements like this and 1366 00:37:15,850 --> 00:37:15,860 electronegative elements like this and 1367 00:37:15,860 --> 00:37:21,920 electronegative elements like this and there may be others here right and one 1368 00:37:21,920 --> 00:37:21,930 there may be others here right and one 1369 00:37:21,930 --> 00:37:26,600 there may be others here right and one molecule in on the other molecule if I 1370 00:37:26,600 --> 00:37:26,610 molecule in on the other molecule if I 1371 00:37:26,610 --> 00:37:31,760 molecule in on the other molecule if I have again lone pair electrons on these 1372 00:37:31,760 --> 00:37:31,770 have again lone pair electrons on these 1373 00:37:31,770 --> 00:37:35,210 have again lone pair electrons on these most electronegative atoms what does 1374 00:37:35,210 --> 00:37:35,220 most electronegative atoms what does 1375 00:37:35,220 --> 00:37:38,120 most electronegative atoms what does that means that means I can have simply 1376 00:37:38,120 --> 00:37:38,130 that means that means I can have simply 1377 00:37:38,130 --> 00:37:42,140 that means that means I can have simply a fluorine here or maybe oxygen maybe 1378 00:37:42,140 --> 00:37:42,150 a fluorine here or maybe oxygen maybe 1379 00:37:42,150 --> 00:37:45,080 a fluorine here or maybe oxygen maybe nitrogen but I have to have lone pair 1380 00:37:45,080 --> 00:37:45,090 nitrogen but I have to have lone pair 1381 00:37:45,090 --> 00:37:45,530 nitrogen but I have to have lone pair electron 1382 00:37:45,530 --> 00:37:45,540 electron 1383 00:37:45,540 --> 00:37:47,720 electron and they will be this will be bonded to 1384 00:37:47,720 --> 00:37:47,730 and they will be this will be bonded to 1385 00:37:47,730 --> 00:37:51,740 and they will be this will be bonded to others like this you know and the same 1386 00:37:51,740 --> 00:37:51,750 others like this you know and the same 1387 00:37:51,750 --> 00:37:54,680 others like this you know and the same things they let's say over here 1388 00:37:54,680 --> 00:37:54,690 things they let's say over here 1389 00:37:54,690 --> 00:37:59,210 things they let's say over here fluorine maybe oxygen maybe nitrogen 1390 00:37:59,210 --> 00:37:59,220 fluorine maybe oxygen maybe nitrogen 1391 00:37:59,220 --> 00:38:02,840 fluorine maybe oxygen maybe nitrogen let's say fluorine and maybe oxygen 1392 00:38:02,840 --> 00:38:02,850 let's say fluorine and maybe oxygen 1393 00:38:02,850 --> 00:38:06,860 let's say fluorine and maybe oxygen nitrogen in fact lone pair electrons on 1394 00:38:06,860 --> 00:38:06,870 nitrogen in fact lone pair electrons on 1395 00:38:06,870 --> 00:38:09,380 nitrogen in fact lone pair electrons on one of the most electronegative elements 1396 00:38:09,380 --> 00:38:09,390 one of the most electronegative elements 1397 00:38:09,390 --> 00:38:12,260 one of the most electronegative elements like this and there is a very strong 1398 00:38:12,260 --> 00:38:12,270 like this and there is a very strong 1399 00:38:12,270 --> 00:38:14,120 like this and there is a very strong attractions actually stronger than 1400 00:38:14,120 --> 00:38:14,130 attractions actually stronger than 1401 00:38:14,130 --> 00:38:17,210 attractions actually stronger than normal dispersion forces and 1402 00:38:17,210 --> 00:38:17,220 normal dispersion forces and 1403 00:38:17,220 --> 00:38:19,640 normal dispersion forces and dipole-dipole forces between this 1404 00:38:19,640 --> 00:38:19,650 dipole-dipole forces between this 1405 00:38:19,650 --> 00:38:23,120 dipole-dipole forces between this hydrogen and this electron pair actually 1406 00:38:23,120 --> 00:38:23,130 hydrogen and this electron pair actually 1407 00:38:23,130 --> 00:38:27,110 hydrogen and this electron pair actually as the book says it is the attraction 1408 00:38:27,110 --> 00:38:27,120 as the book says it is the attraction 1409 00:38:27,120 --> 00:38:29,750 as the book says it is the attraction between that hydrogen and this fluorine 1410 00:38:29,750 --> 00:38:29,760 between that hydrogen and this fluorine 1411 00:38:29,760 --> 00:38:32,690 between that hydrogen and this fluorine but through this electron pairs again 1412 00:38:32,690 --> 00:38:32,700 but through this electron pairs again 1413 00:38:32,700 --> 00:38:38,540 but through this electron pairs again and also this and also this right so 1414 00:38:38,540 --> 00:38:38,550 and also this and also this right so 1415 00:38:38,550 --> 00:38:41,560 and also this and also this right so this kind of attractions are called 1416 00:38:41,560 --> 00:38:41,570 this kind of attractions are called 1417 00:38:41,570 --> 00:38:45,800 this kind of attractions are called hydrogen bonds hydrogen bond now if you 1418 00:38:45,800 --> 00:38:45,810 hydrogen bonds hydrogen bond now if you 1419 00:38:45,810 --> 00:38:47,840 hydrogen bonds hydrogen bond now if you think about this hydrogen bond is 1420 00:38:47,840 --> 00:38:47,850 think about this hydrogen bond is 1421 00:38:47,850 --> 00:38:50,990 think about this hydrogen bond is actually a special type a different type 1422 00:38:50,990 --> 00:38:51,000 actually a special type a different type 1423 00:38:51,000 --> 00:38:55,250 actually a special type a different type of dipole-dipole attractions we can 1424 00:38:55,250 --> 00:38:55,260 of dipole-dipole attractions we can 1425 00:38:55,260 --> 00:38:57,260 of dipole-dipole attractions we can think about that as because when you 1426 00:38:57,260 --> 00:38:57,270 think about that as because when you 1427 00:38:57,270 --> 00:39:00,590 think about that as because when you have the hydrogen bonded to a very 1428 00:39:00,590 --> 00:39:00,600 have the hydrogen bonded to a very 1429 00:39:00,600 --> 00:39:02,720 have the hydrogen bonded to a very electronegative elements one of these 1430 00:39:02,720 --> 00:39:02,730 electronegative elements one of these 1431 00:39:02,730 --> 00:39:05,150 electronegative elements one of these this side of the molecule will be a 1432 00:39:05,150 --> 00:39:05,160 this side of the molecule will be a 1433 00:39:05,160 --> 00:39:09,530 this side of the molecule will be a little bit Delta positive right and this 1434 00:39:09,530 --> 00:39:09,540 little bit Delta positive right and this 1435 00:39:09,540 --> 00:39:11,480 little bit Delta positive right and this will be attracted by this side of the 1436 00:39:11,480 --> 00:39:11,490 will be attracted by this side of the 1437 00:39:11,490 --> 00:39:13,610 will be attracted by this side of the molecule maybe a little bit negative you 1438 00:39:13,610 --> 00:39:13,620 molecule maybe a little bit negative you 1439 00:39:13,620 --> 00:39:15,860 molecule maybe a little bit negative you can say due to the electron pairs and 1440 00:39:15,860 --> 00:39:15,870 can say due to the electron pairs and 1441 00:39:15,870 --> 00:39:19,190 can say due to the electron pairs and they will be attracted and this will 1442 00:39:19,190 --> 00:39:19,200 they will be attracted and this will 1443 00:39:19,200 --> 00:39:23,330 they will be attracted and this will result what we simply call the hydrogen 1444 00:39:23,330 --> 00:39:23,340 result what we simply call the hydrogen 1445 00:39:23,340 --> 00:39:25,490 result what we simply call the hydrogen bonding and this is very very effective 1446 00:39:25,490 --> 00:39:25,500 bonding and this is very very effective 1447 00:39:25,500 --> 00:39:30,380 bonding and this is very very effective actually between the molecules and that 1448 00:39:30,380 --> 00:39:30,390 actually between the molecules and that 1449 00:39:30,390 --> 00:39:36,550 actually between the molecules and that is the reason why we have the higher 1450 00:39:36,550 --> 00:39:36,560 is the reason why we have the higher 1451 00:39:36,560 --> 00:39:41,030 is the reason why we have the higher boiling point for ammonia then expected 1452 00:39:41,030 --> 00:39:41,040 boiling point for ammonia then expected 1453 00:39:41,040 --> 00:39:44,900 boiling point for ammonia then expected and for HF than expected and water than 1454 00:39:44,900 --> 00:39:44,910 and for HF than expected and water than 1455 00:39:44,910 --> 00:39:46,400 and for HF than expected and water than expected remember the boiling point of 1456 00:39:46,400 --> 00:39:46,410 expected remember the boiling point of 1457 00:39:46,410 --> 00:39:48,410 expected remember the boiling point of water is hundred degrees normally the 1458 00:39:48,410 --> 00:39:48,420 water is hundred degrees normally the 1459 00:39:48,420 --> 00:39:50,120 water is hundred degrees normally the boiling point of water should be 1460 00:39:50,120 --> 00:39:50,130 boiling point of water should be 1461 00:39:50,130 --> 00:39:53,270 boiling point of water should be somewhere about over here right this is 1462 00:39:53,270 --> 00:39:53,280 somewhere about over here right this is 1463 00:39:53,280 --> 00:39:57,080 somewhere about over here right this is again about 200 Kelvin that means you 1464 00:39:57,080 --> 00:39:57,090 again about 200 Kelvin that means you 1465 00:39:57,090 --> 00:39:58,470 again about 200 Kelvin that means you know less than 1466 00:39:58,470 --> 00:39:58,480 know less than 1467 00:39:58,480 --> 00:40:01,590 know less than degrees as a matter of fact no this is a 1468 00:40:01,590 --> 00:40:01,600 degrees as a matter of fact no this is a 1469 00:40:01,600 --> 00:40:04,020 degrees as a matter of fact no this is a boiling point yes Kelvin and the ammonia 1470 00:40:04,020 --> 00:40:04,030 boiling point yes Kelvin and the ammonia 1471 00:40:04,030 --> 00:40:07,109 boiling point yes Kelvin and the ammonia should be down here and so on but you 1472 00:40:07,109 --> 00:40:07,119 should be down here and so on but you 1473 00:40:07,119 --> 00:40:10,880 should be down here and so on but you see the methane is here now there is no 1474 00:40:10,880 --> 00:40:10,890 see the methane is here now there is no 1475 00:40:10,890 --> 00:40:13,800 see the methane is here now there is no intermolecular or hydrogen bonding 1476 00:40:13,800 --> 00:40:13,810 intermolecular or hydrogen bonding 1477 00:40:13,810 --> 00:40:21,800 intermolecular or hydrogen bonding actually between two methane molecules 1478 00:40:21,800 --> 00:40:21,810 1479 00:40:21,810 --> 00:40:29,940 let's consider those so methane remember 1480 00:40:29,940 --> 00:40:29,950 let's consider those so methane remember 1481 00:40:29,950 --> 00:40:34,200 let's consider those so methane remember it's a tetrahedral molecule hydrogen 1482 00:40:34,200 --> 00:40:34,210 it's a tetrahedral molecule hydrogen 1483 00:40:34,210 --> 00:40:36,690 it's a tetrahedral molecule hydrogen hydrogen hydrogen like this and there's 1484 00:40:36,690 --> 00:40:36,700 hydrogen hydrogen like this and there's 1485 00:40:36,700 --> 00:40:39,300 hydrogen hydrogen like this and there's another methane here hydrogen hydrogen 1486 00:40:39,300 --> 00:40:39,310 another methane here hydrogen hydrogen 1487 00:40:39,310 --> 00:40:45,359 another methane here hydrogen hydrogen hydrogen and there will be no hydrogen 1488 00:40:45,359 --> 00:40:45,369 hydrogen and there will be no hydrogen 1489 00:40:45,369 --> 00:40:48,120 hydrogen and there will be no hydrogen bonding why because to have a hydrogen 1490 00:40:48,120 --> 00:40:48,130 bonding why because to have a hydrogen 1491 00:40:48,130 --> 00:40:50,849 bonding why because to have a hydrogen bonding I should have a hydrogen bonded 1492 00:40:50,849 --> 00:40:50,859 bonding I should have a hydrogen bonded 1493 00:40:50,859 --> 00:40:53,010 bonding I should have a hydrogen bonded to fluorine oxygen or nitrogen 1494 00:40:53,010 --> 00:40:53,020 to fluorine oxygen or nitrogen 1495 00:40:53,020 --> 00:40:54,390 to fluorine oxygen or nitrogen do I have fluorine oxygen or nitrogen 1496 00:40:54,390 --> 00:40:54,400 do I have fluorine oxygen or nitrogen 1497 00:40:54,400 --> 00:40:57,750 do I have fluorine oxygen or nitrogen here no that means there is no hydrogen 1498 00:40:57,750 --> 00:40:57,760 here no that means there is no hydrogen 1499 00:40:57,760 --> 00:40:59,970 here no that means there is no hydrogen bonding between two fluorine molecule 1500 00:40:59,970 --> 00:40:59,980 bonding between two fluorine molecule 1501 00:40:59,980 --> 00:41:02,970 bonding between two fluorine molecule what is the force of attraction 1502 00:41:02,970 --> 00:41:02,980 what is the force of attraction 1503 00:41:02,980 --> 00:41:08,450 what is the force of attraction intermolecular force between two methane 1504 00:41:08,450 --> 00:41:08,460 1505 00:41:08,460 --> 00:41:11,340 London or dispersion forces right just 1506 00:41:11,340 --> 00:41:11,350 London or dispersion forces right just 1507 00:41:11,350 --> 00:41:13,140 London or dispersion forces right just the dispersion forces because it's 1508 00:41:13,140 --> 00:41:13,150 the dispersion forces because it's 1509 00:41:13,150 --> 00:41:16,010 the dispersion forces because it's nonpolar molecule actually and 1510 00:41:16,010 --> 00:41:16,020 nonpolar molecule actually and 1511 00:41:16,020 --> 00:41:18,300 nonpolar molecule actually and dispersion forces is always there 1512 00:41:18,300 --> 00:41:18,310 dispersion forces is always there 1513 00:41:18,310 --> 00:41:21,810 dispersion forces is always there remember and here in this case the only 1514 00:41:21,810 --> 00:41:21,820 remember and here in this case the only 1515 00:41:21,820 --> 00:41:24,510 remember and here in this case the only force of attraction is dispersion forces 1516 00:41:24,510 --> 00:41:24,520 force of attraction is dispersion forces 1517 00:41:24,520 --> 00:41:27,480 force of attraction is dispersion forces of London forces the same things now if 1518 00:41:27,480 --> 00:41:27,490 of London forces the same things now if 1519 00:41:27,490 --> 00:41:35,849 of London forces the same things now if I simply have the nh3 this is remember 1520 00:41:35,849 --> 00:41:35,859 I simply have the nh3 this is remember 1521 00:41:35,859 --> 00:41:38,160 I simply have the nh3 this is remember tetrahedral geometry this is trigonal 1522 00:41:38,160 --> 00:41:38,170 tetrahedral geometry this is trigonal 1523 00:41:38,170 --> 00:41:40,470 tetrahedral geometry this is trigonal pyramidal geometry right I have the 1524 00:41:40,470 --> 00:41:40,480 pyramidal geometry right I have the 1525 00:41:40,480 --> 00:41:43,410 pyramidal geometry right I have the electron pairs here and now here I have 1526 00:41:43,410 --> 00:41:43,420 electron pairs here and now here I have 1527 00:41:43,420 --> 00:41:52,890 electron pairs here and now here I have another ammonia like this okay and here 1528 00:41:52,890 --> 00:41:52,900 another ammonia like this okay and here 1529 00:41:52,900 --> 00:41:56,000 another ammonia like this okay and here I have the lone pair electrons so now I 1530 00:41:56,000 --> 00:41:56,010 I have the lone pair electrons so now I 1531 00:41:56,010 --> 00:42:00,630 I have the lone pair electrons so now I have all conditions to form hydrogen 1532 00:42:00,630 --> 00:42:00,640 have all conditions to form hydrogen 1533 00:42:00,640 --> 00:42:03,270 have all conditions to form hydrogen bond between two ammonia molecules and 1534 00:42:03,270 --> 00:42:03,280 bond between two ammonia molecules and 1535 00:42:03,280 --> 00:42:06,810 bond between two ammonia molecules and what is that the hydrogen bonded to 1536 00:42:06,810 --> 00:42:06,820 what is that the hydrogen bonded to 1537 00:42:06,820 --> 00:42:10,560 what is that the hydrogen bonded to nitrogen and electron pairs on the 1538 00:42:10,560 --> 00:42:10,570 nitrogen and electron pairs on the 1539 00:42:10,570 --> 00:42:12,390 nitrogen and electron pairs on the nitrogen so there's going to be 1540 00:42:12,390 --> 00:42:12,400 nitrogen so there's going to be 1541 00:42:12,400 --> 00:42:15,420 nitrogen so there's going to be a hydrogen bond between this hydrogen 1542 00:42:15,420 --> 00:42:15,430 a hydrogen bond between this hydrogen 1543 00:42:15,430 --> 00:42:18,150 a hydrogen bond between this hydrogen and that nitrogen over here through that 1544 00:42:18,150 --> 00:42:18,160 and that nitrogen over here through that 1545 00:42:18,160 --> 00:42:20,820 and that nitrogen over here through that lone pair electron lone pair electron so 1546 00:42:20,820 --> 00:42:20,830 lone pair electron lone pair electron so 1547 00:42:20,830 --> 00:42:27,270 lone pair electron lone pair electron so what does that means in addition to the 1548 00:42:27,270 --> 00:42:27,280 what does that means in addition to the 1549 00:42:27,280 --> 00:42:31,080 what does that means in addition to the other intermolecular forces I also have 1550 00:42:31,080 --> 00:42:31,090 other intermolecular forces I also have 1551 00:42:31,090 --> 00:42:37,070 other intermolecular forces I also have hydrogen bond now what others 1552 00:42:37,070 --> 00:42:37,080 hydrogen bond now what others 1553 00:42:37,080 --> 00:42:39,870 hydrogen bond now what others intermolecular force will be operating 1554 00:42:39,870 --> 00:42:39,880 intermolecular force will be operating 1555 00:42:39,880 --> 00:42:43,940 intermolecular force will be operating in ammonia first of all will it have 1556 00:42:43,940 --> 00:42:43,950 in ammonia first of all will it have 1557 00:42:43,950 --> 00:42:47,280 in ammonia first of all will it have London dispersion forces yes 1558 00:42:47,280 --> 00:42:47,290 London dispersion forces yes 1559 00:42:47,290 --> 00:42:49,650 London dispersion forces yes remember dispersion forces exists 1560 00:42:49,650 --> 00:42:49,660 remember dispersion forces exists 1561 00:42:49,660 --> 00:42:53,070 remember dispersion forces exists between all molecules now second do I 1562 00:42:53,070 --> 00:42:53,080 between all molecules now second do I 1563 00:42:53,080 --> 00:42:57,660 between all molecules now second do I have a dipole-dipole attractions ammonia 1564 00:42:57,660 --> 00:42:57,670 have a dipole-dipole attractions ammonia 1565 00:42:57,670 --> 00:43:00,030 have a dipole-dipole attractions ammonia is a polar molecule right even though 1566 00:43:00,030 --> 00:43:00,040 is a polar molecule right even though 1567 00:43:00,040 --> 00:43:02,040 is a polar molecule right even though the polarity is very very low but it's a 1568 00:43:02,040 --> 00:43:02,050 the polarity is very very low but it's a 1569 00:43:02,050 --> 00:43:05,370 the polarity is very very low but it's a polar molecule is not much but this is 1570 00:43:05,370 --> 00:43:05,380 polar molecule is not much but this is 1571 00:43:05,380 --> 00:43:08,970 polar molecule is not much but this is this hydrogen bond is the main force of 1572 00:43:08,970 --> 00:43:08,980 this hydrogen bond is the main force of 1573 00:43:08,980 --> 00:43:12,240 this hydrogen bond is the main force of intermolecular attraction which changes 1574 00:43:12,240 --> 00:43:12,250 intermolecular attraction which changes 1575 00:43:12,250 --> 00:43:14,790 intermolecular attraction which changes the boiling point simply in way of 1576 00:43:14,790 --> 00:43:14,800 the boiling point simply in way of 1577 00:43:14,800 --> 00:43:16,650 the boiling point simply in way of increase in the boiling point of ammonia 1578 00:43:16,650 --> 00:43:16,660 increase in the boiling point of ammonia 1579 00:43:16,660 --> 00:43:20,820 increase in the boiling point of ammonia then we expected only based on the 1580 00:43:20,820 --> 00:43:20,830 then we expected only based on the 1581 00:43:20,830 --> 00:43:24,030 then we expected only based on the dispersion forces again right now same 1582 00:43:24,030 --> 00:43:24,040 dispersion forces again right now same 1583 00:43:24,040 --> 00:43:26,460 dispersion forces again right now same thing is true for the hydrogen fluoride 1584 00:43:26,460 --> 00:43:26,470 thing is true for the hydrogen fluoride 1585 00:43:26,470 --> 00:43:29,520 thing is true for the hydrogen fluoride in a hydrogen fluoride we have simply 1586 00:43:29,520 --> 00:43:29,530 in a hydrogen fluoride we have simply 1587 00:43:29,530 --> 00:43:32,580 in a hydrogen fluoride we have simply hydrogen bonded to the fluorine and then 1588 00:43:32,580 --> 00:43:32,590 hydrogen bonded to the fluorine and then 1589 00:43:32,590 --> 00:43:37,860 hydrogen bonded to the fluorine and then we have fluorine simply have lone pair 1590 00:43:37,860 --> 00:43:37,870 we have fluorine simply have lone pair 1591 00:43:37,870 --> 00:43:40,200 we have fluorine simply have lone pair electrons actually three lone pair 1592 00:43:40,200 --> 00:43:40,210 electrons actually three lone pair 1593 00:43:40,210 --> 00:43:42,330 electrons actually three lone pair electrons and I will have very strong 1594 00:43:42,330 --> 00:43:42,340 electrons and I will have very strong 1595 00:43:42,340 --> 00:43:45,690 electrons and I will have very strong simply hydrogen bonding between this 1596 00:43:45,690 --> 00:43:45,700 simply hydrogen bonding between this 1597 00:43:45,700 --> 00:43:47,880 simply hydrogen bonding between this hydrogen and this fluorine now this 1598 00:43:47,880 --> 00:43:47,890 hydrogen and this fluorine now this 1599 00:43:47,890 --> 00:43:50,040 hydrogen and this fluorine now this hydrogen and another fluorine this lone 1600 00:43:50,040 --> 00:43:50,050 hydrogen and another fluorine this lone 1601 00:43:50,050 --> 00:43:52,260 hydrogen and another fluorine this lone pair another hydrogen now here I have 1602 00:43:52,260 --> 00:43:52,270 pair another hydrogen now here I have 1603 00:43:52,270 --> 00:43:56,730 pair another hydrogen now here I have the simply like this and actually the 1604 00:43:56,730 --> 00:43:56,740 the simply like this and actually the 1605 00:43:56,740 --> 00:43:59,910 the simply like this and actually the structure of the HF liquid HF is zigzag 1606 00:43:59,910 --> 00:43:59,920 structure of the HF liquid HF is zigzag 1607 00:43:59,920 --> 00:44:02,280 structure of the HF liquid HF is zigzag type to get a maximum hydrogen bonding 1608 00:44:02,280 --> 00:44:02,290 type to get a maximum hydrogen bonding 1609 00:44:02,290 --> 00:44:06,090 type to get a maximum hydrogen bonding and so that hydrogen bonding forces in 1610 00:44:06,090 --> 00:44:06,100 and so that hydrogen bonding forces in 1611 00:44:06,100 --> 00:44:10,730 and so that hydrogen bonding forces in fact increases the boiling point of HF 1612 00:44:10,730 --> 00:44:10,740 fact increases the boiling point of HF 1613 00:44:10,740 --> 00:44:15,300 fact increases the boiling point of HF compared to the HCL actually much higher 1614 00:44:15,300 --> 00:44:15,310 compared to the HCL actually much higher 1615 00:44:15,310 --> 00:44:18,600 compared to the HCL actually much higher than we expected now for the water 1616 00:44:18,600 --> 00:44:18,610 than we expected now for the water 1617 00:44:18,610 --> 00:44:23,450 than we expected now for the water another is again let's take the water 1618 00:44:23,450 --> 00:44:23,460 another is again let's take the water 1619 00:44:23,460 --> 00:44:26,350 another is again let's take the water remember we have the electron pairs 1620 00:44:26,350 --> 00:44:26,360 remember we have the electron pairs 1621 00:44:26,360 --> 00:44:28,570 remember we have the electron pairs the oxygen and now we have hydrogen 1622 00:44:28,570 --> 00:44:28,580 the oxygen and now we have hydrogen 1623 00:44:28,580 --> 00:44:31,510 the oxygen and now we have hydrogen bonded to the oxygen um and I also have 1624 00:44:31,510 --> 00:44:31,520 bonded to the oxygen um and I also have 1625 00:44:31,520 --> 00:44:34,810 bonded to the oxygen um and I also have electron pairs on the hydrogen lone 1626 00:44:34,810 --> 00:44:34,820 electron pairs on the hydrogen lone 1627 00:44:34,820 --> 00:44:36,880 electron pairs on the hydrogen lone pairs so there's going to be again 1628 00:44:36,880 --> 00:44:36,890 pairs so there's going to be again 1629 00:44:36,890 --> 00:44:40,330 pairs so there's going to be again hydrogen bond between this oxygen and 1630 00:44:40,330 --> 00:44:40,340 hydrogen bond between this oxygen and 1631 00:44:40,340 --> 00:44:42,940 hydrogen bond between this oxygen and that hydrogen through the lone pair 1632 00:44:42,940 --> 00:44:42,950 that hydrogen through the lone pair 1633 00:44:42,950 --> 00:44:46,560 that hydrogen through the lone pair electrons see again to have an 1634 00:44:46,560 --> 00:44:46,570 electrons see again to have an 1635 00:44:46,570 --> 00:44:49,660 electrons see again to have an intermolecular attraction as hydrogen 1636 00:44:49,660 --> 00:44:49,670 intermolecular attraction as hydrogen 1637 00:44:49,670 --> 00:44:53,110 intermolecular attraction as hydrogen bonding between two molecules you have 1638 00:44:53,110 --> 00:44:53,120 bonding between two molecules you have 1639 00:44:53,120 --> 00:44:54,970 bonding between two molecules you have to have a hydrogen bonded to most 1640 00:44:54,970 --> 00:44:54,980 to have a hydrogen bonded to most 1641 00:44:54,980 --> 00:44:56,770 to have a hydrogen bonded to most electronegative element on one molecule 1642 00:44:56,770 --> 00:44:56,780 electronegative element on one molecule 1643 00:44:56,780 --> 00:44:58,960 electronegative element on one molecule and then you should also have lone pair 1644 00:44:58,960 --> 00:44:58,970 and then you should also have lone pair 1645 00:44:58,970 --> 00:45:01,240 and then you should also have lone pair electrons again on the most 1646 00:45:01,240 --> 00:45:01,250 electrons again on the most 1647 00:45:01,250 --> 00:45:02,770 electrons again on the most electronegative elements those are 1648 00:45:02,770 --> 00:45:02,780 electronegative elements those are 1649 00:45:02,780 --> 00:45:05,530 electronegative elements those are fluorine oxygen and nitrogen right to 1650 00:45:05,530 --> 00:45:05,540 fluorine oxygen and nitrogen right to 1651 00:45:05,540 --> 00:45:07,480 fluorine oxygen and nitrogen right to have the hydrogen bonded otherwise we 1652 00:45:07,480 --> 00:45:07,490 have the hydrogen bonded otherwise we 1653 00:45:07,490 --> 00:45:10,800 have the hydrogen bonded otherwise we will not have hydrogen bonded so this 1654 00:45:10,800 --> 00:45:10,810 will not have hydrogen bonded so this 1655 00:45:10,810 --> 00:45:13,120 will not have hydrogen bonded so this unexpected behavior or much higher 1656 00:45:13,120 --> 00:45:13,130 unexpected behavior or much higher 1657 00:45:13,130 --> 00:45:16,150 unexpected behavior or much higher boiling points of ammonia HF and water 1658 00:45:16,150 --> 00:45:16,160 boiling points of ammonia HF and water 1659 00:45:16,160 --> 00:45:20,290 boiling points of ammonia HF and water is due to the hydrogen bonding possible 1660 00:45:20,290 --> 00:45:20,300 is due to the hydrogen bonding possible 1661 00:45:20,300 --> 00:45:22,870 is due to the hydrogen bonding possible between the molecules of these liquids 1662 00:45:22,870 --> 00:45:22,880 between the molecules of these liquids 1663 00:45:22,880 --> 00:45:25,360 between the molecules of these liquids actually which is not present in methane 1664 00:45:25,360 --> 00:45:25,370 actually which is not present in methane 1665 00:45:25,370 --> 00:45:33,010 actually which is not present in methane which is not present in methane okay 1666 00:45:33,010 --> 00:45:33,020 which is not present in methane okay 1667 00:45:33,020 --> 00:45:35,800 which is not present in methane okay this these are again the same type of 1668 00:45:35,800 --> 00:45:35,810 this these are again the same type of 1669 00:45:35,810 --> 00:45:37,690 this these are again the same type of thing which shows how the hydrogen 1670 00:45:37,690 --> 00:45:37,700 thing which shows how the hydrogen 1671 00:45:37,700 --> 00:45:39,730 thing which shows how the hydrogen bonding will simply take place the 1672 00:45:39,730 --> 00:45:39,740 bonding will simply take place the 1673 00:45:39,740 --> 00:45:41,590 bonding will simply take place the dipole-dipole interaction experiences 1674 00:45:41,590 --> 00:45:41,600 dipole-dipole interaction experiences 1675 00:45:41,600 --> 00:45:43,420 dipole-dipole interaction experiences when hydrogen is bonded to nitrogen 1676 00:45:43,420 --> 00:45:43,430 when hydrogen is bonded to nitrogen 1677 00:45:43,430 --> 00:45:47,860 when hydrogen is bonded to nitrogen oxygen or f are usually strong we call 1678 00:45:47,860 --> 00:45:47,870 oxygen or f are usually strong we call 1679 00:45:47,870 --> 00:45:49,240 oxygen or f are usually strong we call these interactions hydrogen bonds it 1680 00:45:49,240 --> 00:45:49,250 these interactions hydrogen bonds it 1681 00:45:49,250 --> 00:45:51,100 these interactions hydrogen bonds it says hydrogen bonds is an attraction 1682 00:45:51,100 --> 00:45:51,110 says hydrogen bonds is an attraction 1683 00:45:51,110 --> 00:45:53,560 says hydrogen bonds is an attraction between a hydrogen atom attached to a 1684 00:45:53,560 --> 00:45:53,570 between a hydrogen atom attached to a 1685 00:45:53,570 --> 00:45:56,320 between a hydrogen atom attached to a highly electronegative atom and nearby 1686 00:45:56,320 --> 00:45:56,330 highly electronegative atom and nearby 1687 00:45:56,330 --> 00:45:59,080 highly electronegative atom and nearby now here I didn't like this this is this 1688 00:45:59,080 --> 00:45:59,090 now here I didn't like this this is this 1689 00:45:59,090 --> 00:46:02,200 now here I didn't like this this is this is not really true 1690 00:46:02,200 --> 00:46:02,210 is not really true 1691 00:46:02,210 --> 00:46:04,540 is not really true here it says attached to a highly 1692 00:46:04,540 --> 00:46:04,550 here it says attached to a highly 1693 00:46:04,550 --> 00:46:06,430 here it says attached to a highly electronegative atom right I have to 1694 00:46:06,430 --> 00:46:06,440 electronegative atom right I have to 1695 00:46:06,440 --> 00:46:07,960 electronegative atom right I have to have a hydrogen bonded to nitrogen 1696 00:46:07,960 --> 00:46:07,970 have a hydrogen bonded to nitrogen 1697 00:46:07,970 --> 00:46:10,120 have a hydrogen bonded to nitrogen fluorine or oxygen electronegative 1698 00:46:10,120 --> 00:46:10,130 fluorine or oxygen electronegative 1699 00:46:10,130 --> 00:46:12,340 fluorine or oxygen electronegative that's what means atom and nearby small 1700 00:46:12,340 --> 00:46:12,350 that's what means atom and nearby small 1701 00:46:12,350 --> 00:46:14,520 that's what means atom and nearby small electronegative atom in another molecule 1702 00:46:14,520 --> 00:46:14,530 electronegative atom in another molecule 1703 00:46:14,530 --> 00:46:18,010 electronegative atom in another molecule or a chemical group that means it says 1704 00:46:18,010 --> 00:46:18,020 or a chemical group that means it says 1705 00:46:18,020 --> 00:46:20,530 or a chemical group that means it says there must be a nitrogen oxygen or 1706 00:46:20,530 --> 00:46:20,540 there must be a nitrogen oxygen or 1707 00:46:20,540 --> 00:46:23,380 there must be a nitrogen oxygen or fluorine on another molecule but this is 1708 00:46:23,380 --> 00:46:23,390 fluorine on another molecule but this is 1709 00:46:23,390 --> 00:46:24,130 fluorine on another molecule but this is not enough 1710 00:46:24,130 --> 00:46:24,140 not enough 1711 00:46:24,140 --> 00:46:28,090 not enough why we should also say that there must 1712 00:46:28,090 --> 00:46:28,100 why we should also say that there must 1713 00:46:28,100 --> 00:46:32,890 why we should also say that there must be lone pair electrons on those nitrogen 1714 00:46:32,890 --> 00:46:32,900 be lone pair electrons on those nitrogen 1715 00:46:32,900 --> 00:46:35,620 be lone pair electrons on those nitrogen in fact fluorine oxygen to have a 1716 00:46:35,620 --> 00:46:35,630 in fact fluorine oxygen to have a 1717 00:46:35,630 --> 00:46:38,200 in fact fluorine oxygen to have a hydrogen bond if you don't have the lone 1718 00:46:38,200 --> 00:46:38,210 hydrogen bond if you don't have the lone 1719 00:46:38,210 --> 00:46:39,590 hydrogen bond if you don't have the lone pair electrons on 1720 00:46:39,590 --> 00:46:39,600 pair electrons on 1721 00:46:39,600 --> 00:46:43,030 pair electrons on nitrogen oxygen and fluorine it will not 1722 00:46:43,030 --> 00:46:43,040 nitrogen oxygen and fluorine it will not 1723 00:46:43,040 --> 00:46:47,330 nitrogen oxygen and fluorine it will not form hydrogen bond so that is we have to 1724 00:46:47,330 --> 00:46:47,340 form hydrogen bond so that is we have to 1725 00:46:47,340 --> 00:46:50,410 form hydrogen bond so that is we have to be careful here remember that the 1726 00:46:50,410 --> 00:46:50,420 be careful here remember that the 1727 00:46:50,420 --> 00:46:53,060 be careful here remember that the possibility of hydrogen bonding is 1728 00:46:53,060 --> 00:46:53,070 possibility of hydrogen bonding is 1729 00:46:53,070 --> 00:46:54,980 possibility of hydrogen bonding is possible if you have lone pair electrons 1730 00:46:54,980 --> 00:46:54,990 possible if you have lone pair electrons 1731 00:46:54,990 --> 00:46:57,050 possible if you have lone pair electrons on most electronegative on one molecule 1732 00:46:57,050 --> 00:46:57,060 on most electronegative on one molecule 1733 00:46:57,060 --> 00:46:59,660 on most electronegative on one molecule and again if you have hydrogen bonded to 1734 00:46:59,660 --> 00:46:59,670 and again if you have hydrogen bonded to 1735 00:46:59,670 --> 00:47:05,600 and again if you have hydrogen bonded to the most electronegative elements okay 1736 00:47:05,600 --> 00:47:05,610 the most electronegative elements okay 1737 00:47:05,610 --> 00:47:08,390 the most electronegative elements okay now this is simply says that the 1738 00:47:08,390 --> 00:47:08,400 now this is simply says that the 1739 00:47:08,400 --> 00:47:13,090 now this is simply says that the hydrogen bonding is more or less like a 1740 00:47:13,090 --> 00:47:13,100 hydrogen bonding is more or less like a 1741 00:47:13,100 --> 00:47:16,790 hydrogen bonding is more or less like a dipole-dipole attractions yes you can 1742 00:47:16,790 --> 00:47:16,800 dipole-dipole attractions yes you can 1743 00:47:16,800 --> 00:47:17,690 dipole-dipole attractions yes you can look it that way 1744 00:47:17,690 --> 00:47:17,700 look it that way 1745 00:47:17,700 --> 00:47:20,780 look it that way hydrogen bond arises in part from the 1746 00:47:20,780 --> 00:47:20,790 hydrogen bond arises in part from the 1747 00:47:20,790 --> 00:47:22,400 hydrogen bond arises in part from the high electronegative the Oh hydrogen 1748 00:47:22,400 --> 00:47:22,410 high electronegative the Oh hydrogen 1749 00:47:22,410 --> 00:47:25,820 high electronegative the Oh hydrogen nitrogen and fluorine because those are 1750 00:47:25,820 --> 00:47:25,830 nitrogen and fluorine because those are 1751 00:47:25,830 --> 00:47:27,680 nitrogen and fluorine because those are the most electronegative these atoms 1752 00:47:27,680 --> 00:47:27,690 the most electronegative these atoms 1753 00:47:27,690 --> 00:47:31,760 the most electronegative these atoms interact with nearly bare nucleus which 1754 00:47:31,760 --> 00:47:31,770 interact with nearly bare nucleus which 1755 00:47:31,770 --> 00:47:35,180 interact with nearly bare nucleus which contains one proton simply inform the 1756 00:47:35,180 --> 00:47:35,190 contains one proton simply inform the 1757 00:47:35,190 --> 00:47:36,830 contains one proton simply inform the hydrogen bonding but there have to be 1758 00:47:36,830 --> 00:47:36,840 hydrogen bonding but there have to be 1759 00:47:36,840 --> 00:47:38,960 hydrogen bonding but there have to be lone pair electrons if there's no lone 1760 00:47:38,960 --> 00:47:38,970 lone pair electrons if there's no lone 1761 00:47:38,970 --> 00:47:44,990 lone pair electrons if there's no lone pair electrons no hydrogen bonds okay I 1762 00:47:44,990 --> 00:47:45,000 pair electrons no hydrogen bonds okay I 1763 00:47:45,000 --> 00:47:50,810 pair electrons no hydrogen bonds okay I guess we will stop here question