1 00:00:06,990 --> 00:00:09,440 stabilize knickers that means the 2 00:00:09,440 --> 00:00:09,450 stabilize knickers that means the 3 00:00:09,450 --> 00:00:11,150 stabilize knickers that means the neutron to proton ratio it becomes 4 00:00:11,150 --> 00:00:11,160 neutron to proton ratio it becomes 5 00:00:11,160 --> 00:00:14,060 neutron to proton ratio it becomes greater than one the shaded region in 6 00:00:14,060 --> 00:00:14,070 greater than one the shaded region in 7 00:00:14,070 --> 00:00:16,070 greater than one the shaded region in the figure is called the belt of 8 00:00:16,070 --> 00:00:16,080 the figure is called the belt of 9 00:00:16,080 --> 00:00:18,290 the figure is called the belt of stability this is what it is the belt of 10 00:00:18,290 --> 00:00:18,300 stability this is what it is the belt of 11 00:00:18,300 --> 00:00:18,980 stability this is what it is the belt of stability 12 00:00:18,980 --> 00:00:18,990 stability 13 00:00:18,990 --> 00:00:22,940 stability it shows what nuclides would be stable 14 00:00:22,940 --> 00:00:22,950 it shows what nuclides would be stable 15 00:00:22,950 --> 00:00:26,019 it shows what nuclides would be stable right and these are the stable nuclei x' 16 00:00:26,019 --> 00:00:26,029 right and these are the stable nuclei x' 17 00:00:26,029 --> 00:00:31,820 right and these are the stable nuclei x' now let's go to the next one to find out 18 00:00:31,820 --> 00:00:31,830 now let's go to the next one to find out 19 00:00:31,830 --> 00:00:34,520 now let's go to the next one to find out if you're given any quads and find out 20 00:00:34,520 --> 00:00:34,530 if you're given any quads and find out 21 00:00:34,530 --> 00:00:36,380 if you're given any quads and find out whether that nuclei will be stable or 22 00:00:36,380 --> 00:00:36,390 whether that nuclei will be stable or 23 00:00:36,390 --> 00:00:38,869 whether that nuclei will be stable or not stable what you have to do is you 24 00:00:38,869 --> 00:00:38,879 not stable what you have to do is you 25 00:00:38,879 --> 00:00:40,549 not stable what you have to do is you have to find out the number of neutrons 26 00:00:40,549 --> 00:00:40,559 have to find out the number of neutrons 27 00:00:40,559 --> 00:00:42,770 have to find out the number of neutrons and the number of protons and you find 28 00:00:42,770 --> 00:00:42,780 and the number of protons and you find 29 00:00:42,780 --> 00:00:45,680 and the number of protons and you find out the place of that nuclides on this 30 00:00:45,680 --> 00:00:45,690 out the place of that nuclides on this 31 00:00:45,690 --> 00:00:47,899 out the place of that nuclides on this diagram here let's say if it is 32 00:00:47,899 --> 00:00:47,909 diagram here let's say if it is 33 00:00:47,909 --> 00:00:50,270 diagram here let's say if it is somewhere over here that means on the 34 00:00:50,270 --> 00:00:50,280 somewhere over here that means on the 35 00:00:50,280 --> 00:00:54,049 somewhere over here that means on the left side of this zone stability zone on 36 00:00:54,049 --> 00:00:54,059 left side of this zone stability zone on 37 00:00:54,059 --> 00:00:55,609 left side of this zone stability zone on the left side what is that means that 38 00:00:55,609 --> 00:00:55,619 the left side what is that means that 39 00:00:55,619 --> 00:00:59,770 the left side what is that means that means that nuclides has too much 40 00:00:59,770 --> 00:00:59,780 means that nuclides has too much 41 00:00:59,780 --> 00:01:04,429 means that nuclides has too much neutrons so it will be K to decrease the 42 00:01:04,429 --> 00:01:04,439 neutrons so it will be K to decrease the 43 00:01:04,439 --> 00:01:06,800 neutrons so it will be K to decrease the number of neutrons and increase the 44 00:01:06,800 --> 00:01:06,810 number of neutrons and increase the 45 00:01:06,810 --> 00:01:10,010 number of neutrons and increase the number of protons right and how that 46 00:01:10,010 --> 00:01:10,020 number of protons right and how that 47 00:01:10,020 --> 00:01:12,080 number of protons right and how that would be possible it would be possible 48 00:01:12,080 --> 00:01:12,090 would be possible it would be possible 49 00:01:12,090 --> 00:01:15,800 would be possible it would be possible by beta emission that means any nuclei 50 00:01:15,800 --> 00:01:15,810 by beta emission that means any nuclei 51 00:01:15,810 --> 00:01:19,789 by beta emission that means any nuclei that will have proton Neutron numbers in 52 00:01:19,789 --> 00:01:19,799 that will have proton Neutron numbers in 53 00:01:19,799 --> 00:01:23,230 that will have proton Neutron numbers in this region here there they will simply 54 00:01:23,230 --> 00:01:23,240 this region here there they will simply 55 00:01:23,240 --> 00:01:28,219 this region here there they will simply give beta radiation that means given 56 00:01:28,219 --> 00:01:28,229 give beta radiation that means given 57 00:01:28,229 --> 00:01:32,419 give beta radiation that means given electron and convert a neutron to a 58 00:01:32,419 --> 00:01:32,429 electron and convert a neutron to a 59 00:01:32,429 --> 00:01:35,480 electron and convert a neutron to a proton and this way decrease the neutron 60 00:01:35,480 --> 00:01:35,490 proton and this way decrease the neutron 61 00:01:35,490 --> 00:01:38,599 proton and this way decrease the neutron to proton ratio and comes to this belt 62 00:01:38,599 --> 00:01:38,609 to proton ratio and comes to this belt 63 00:01:38,609 --> 00:01:42,319 to proton ratio and comes to this belt over here to the stable zone here like 64 00:01:42,319 --> 00:01:42,329 over here to the stable zone here like 65 00:01:42,329 --> 00:01:45,260 over here to the stable zone here like this now if it is on this side of this 66 00:01:45,260 --> 00:01:45,270 this now if it is on this side of this 67 00:01:45,270 --> 00:01:48,349 this now if it is on this side of this stable zone then what will happen in 68 00:01:48,349 --> 00:01:48,359 stable zone then what will happen in 69 00:01:48,359 --> 00:01:50,569 stable zone then what will happen in that case that means they have too much 70 00:01:50,569 --> 00:01:50,579 that case that means they have too much 71 00:01:50,579 --> 00:01:54,459 that case that means they have too much proton compared to Neutron so the decay 72 00:01:54,459 --> 00:01:54,469 proton compared to Neutron so the decay 73 00:01:54,469 --> 00:01:59,840 proton compared to Neutron so the decay will be type of decay that will decrease 74 00:01:59,840 --> 00:01:59,850 will be type of decay that will decrease 75 00:01:59,850 --> 00:02:01,969 will be type of decay that will decrease the number of proton and increase the 76 00:02:01,969 --> 00:02:01,979 the number of proton and increase the 77 00:02:01,979 --> 00:02:03,739 the number of proton and increase the number of neutron and that will be 78 00:02:03,739 --> 00:02:03,749 number of neutron and that will be 79 00:02:03,749 --> 00:02:08,230 number of neutron and that will be positron emission decay or it will be 80 00:02:08,230 --> 00:02:08,240 positron emission decay or it will be 81 00:02:08,240 --> 00:02:11,420 positron emission decay or it will be electron capture both the positron 82 00:02:11,420 --> 00:02:11,430 electron capture both the positron 83 00:02:11,430 --> 00:02:13,520 electron capture both the positron emission and the electron capture will 84 00:02:13,520 --> 00:02:13,530 emission and the electron capture will 85 00:02:13,530 --> 00:02:16,040 emission and the electron capture will decrease the number of protons by one 86 00:02:16,040 --> 00:02:16,050 decrease the number of protons by one 87 00:02:16,050 --> 00:02:17,990 decrease the number of protons by one and increase the number of neutrons that 88 00:02:17,990 --> 00:02:18,000 and increase the number of neutrons that 89 00:02:18,000 --> 00:02:20,839 and increase the number of neutrons that means any on this side here 90 00:02:20,839 --> 00:02:20,849 means any on this side here 91 00:02:20,849 --> 00:02:25,970 means any on this side here positron capture simply or it may be 92 00:02:25,970 --> 00:02:25,980 positron capture simply or it may be 93 00:02:25,980 --> 00:02:29,209 positron capture simply or it may be positron emission any over here will be 94 00:02:29,209 --> 00:02:29,219 positron emission any over here will be 95 00:02:29,219 --> 00:02:31,369 positron emission any over here will be the beta emission to reach to the 96 00:02:31,369 --> 00:02:31,379 the beta emission to reach to the 97 00:02:31,379 --> 00:02:33,979 the beta emission to reach to the stability but if it is too high over 98 00:02:33,979 --> 00:02:33,989 stability but if it is too high over 99 00:02:33,989 --> 00:02:35,360 stability but if it is too high over here actually 100 00:02:35,360 --> 00:02:35,370 here actually 101 00:02:35,370 --> 00:02:40,970 here actually then big particles need to come out from 102 00:02:40,970 --> 00:02:40,980 then big particles need to come out from 103 00:02:40,980 --> 00:02:43,099 then big particles need to come out from those nuclearized unstable nucleus such 104 00:02:43,099 --> 00:02:43,109 those nuclearized unstable nucleus such 105 00:02:43,109 --> 00:02:45,229 those nuclearized unstable nucleus such as alpha particles as a matter of fact 106 00:02:45,229 --> 00:02:45,239 as alpha particles as a matter of fact 107 00:02:45,239 --> 00:02:49,460 as alpha particles as a matter of fact and to reach to more stable state nor 108 00:02:49,460 --> 00:02:49,470 and to reach to more stable state nor 109 00:02:49,470 --> 00:02:52,089 and to reach to more stable state nor stable nucleus as a matter of fact then 110 00:02:52,089 --> 00:02:52,099 stable nucleus as a matter of fact then 111 00:02:52,099 --> 00:02:55,009 stable nucleus as a matter of fact then so the nuclei below the belt have too 112 00:02:55,009 --> 00:02:55,019 so the nuclei below the belt have too 113 00:02:55,019 --> 00:02:57,349 so the nuclei below the belt have too many protons so they tend to become more 114 00:02:57,349 --> 00:02:57,359 many protons so they tend to become more 115 00:02:57,359 --> 00:02:59,899 many protons so they tend to become more stable by positron emission or electron 116 00:02:59,899 --> 00:02:59,909 stable by positron emission or electron 117 00:02:59,909 --> 00:03:02,479 stable by positron emission or electron capture and here alpha beta particles 118 00:03:02,479 --> 00:03:02,489 capture and here alpha beta particles 119 00:03:02,489 --> 00:03:14,030 capture and here alpha beta particles actually like this yes question beta 120 00:03:14,030 --> 00:03:14,040 actually like this yes question beta 121 00:03:14,040 --> 00:03:18,369 actually like this yes question beta particle comes out in the orbital don't 122 00:03:18,369 --> 00:03:18,379 particle comes out in the orbital don't 123 00:03:18,379 --> 00:03:25,699 particle comes out in the orbital don't now that that we know we can't really 124 00:03:25,699 --> 00:03:25,709 now that that we know we can't really 125 00:03:25,709 --> 00:03:28,099 now that that we know we can't really say alright I see what you mean what 126 00:03:28,099 --> 00:03:28,109 say alright I see what you mean what 127 00:03:28,109 --> 00:03:30,619 say alright I see what you mean what you're saying is this right now you're 128 00:03:30,619 --> 00:03:30,629 you're saying is this right now you're 129 00:03:30,629 --> 00:03:34,909 you're saying is this right now you're saying that if a neutron actually if a 130 00:03:34,909 --> 00:03:34,919 saying that if a neutron actually if a 131 00:03:34,919 --> 00:03:39,589 saying that if a neutron actually if a nucleus gives a electron and we 132 00:03:39,589 --> 00:03:39,599 nucleus gives a electron and we 133 00:03:39,599 --> 00:03:42,349 nucleus gives a electron and we visualize it as a proton is converted to 134 00:03:42,349 --> 00:03:42,359 visualize it as a proton is converted to 135 00:03:42,359 --> 00:03:45,080 visualize it as a proton is converted to Neutron is converted to the proton so 136 00:03:45,080 --> 00:03:45,090 Neutron is converted to the proton so 137 00:03:45,090 --> 00:03:49,099 Neutron is converted to the proton so that means that the product nucleoid 138 00:03:49,099 --> 00:03:49,109 that means that the product nucleoid 139 00:03:49,109 --> 00:03:52,069 that means that the product nucleoid will have one more proton so that atom 140 00:03:52,069 --> 00:03:52,079 will have one more proton so that atom 141 00:03:52,079 --> 00:03:54,110 will have one more proton so that atom should have one more electron now we 142 00:03:54,110 --> 00:03:54,120 should have one more electron now we 143 00:03:54,120 --> 00:03:57,170 should have one more electron now we don't know we can't really tell whether 144 00:03:57,170 --> 00:03:57,180 don't know we can't really tell whether 145 00:03:57,180 --> 00:03:59,149 don't know we can't really tell whether the electron there is the one which 146 00:03:59,149 --> 00:03:59,159 the electron there is the one which 147 00:03:59,159 --> 00:04:13,030 the electron there is the one which comes out from the nucleus 148 00:04:13,030 --> 00:04:13,040 149 00:04:13,040 --> 00:04:15,589 new single there is no single Neutron at 150 00:04:15,589 --> 00:04:15,599 new single there is no single Neutron at 151 00:04:15,599 --> 00:04:21,640 new single there is no single Neutron at the menu or single Neutron yes by given 152 00:04:21,640 --> 00:04:21,650 153 00:04:21,650 --> 00:04:24,950 that yeah that will be a proton a proton 154 00:04:24,950 --> 00:04:24,960 that yeah that will be a proton a proton 155 00:04:24,960 --> 00:04:26,750 that yeah that will be a proton a proton is actually hydrogen yeah that that you 156 00:04:26,750 --> 00:04:26,760 is actually hydrogen yeah that that you 157 00:04:26,760 --> 00:04:30,560 is actually hydrogen yeah that that you can look it that way but if you consider 158 00:04:30,560 --> 00:04:30,570 can look it that way but if you consider 159 00:04:30,570 --> 00:04:33,110 can look it that way but if you consider the mini proton many electron atom 160 00:04:33,110 --> 00:04:33,120 the mini proton many electron atom 161 00:04:33,120 --> 00:04:35,840 the mini proton many electron atom nucleus right when an electron beta 162 00:04:35,840 --> 00:04:35,850 nucleus right when an electron beta 163 00:04:35,850 --> 00:04:38,960 nucleus right when an electron beta emission is given that electron comes 164 00:04:38,960 --> 00:04:38,970 emission is given that electron comes 165 00:04:38,970 --> 00:04:41,840 emission is given that electron comes out from that atom it doesn't stay there 166 00:04:41,840 --> 00:04:41,850 out from that atom it doesn't stay there 167 00:04:41,850 --> 00:04:44,840 out from that atom it doesn't stay there because you see the emission beta 168 00:04:44,840 --> 00:04:44,850 because you see the emission beta 169 00:04:44,850 --> 00:04:47,140 because you see the emission beta emission effect of beta emission 170 00:04:47,140 --> 00:04:47,150 emission effect of beta emission 171 00:04:47,150 --> 00:04:50,110 emission effect of beta emission remember we gave the penetration 172 00:04:50,110 --> 00:04:50,120 remember we gave the penetration 173 00:04:50,120 --> 00:04:52,580 remember we gave the penetration penetrating power off of the particles 174 00:04:52,580 --> 00:04:52,590 penetrating power off of the particles 175 00:04:52,590 --> 00:04:56,719 penetrating power off of the particles and for the electron we said 100 for the 176 00:04:56,719 --> 00:04:56,729 and for the electron we said 100 for the 177 00:04:56,729 --> 00:05:00,590 and for the electron we said 100 for the alpha particle was just one anyhow or 10 178 00:05:00,590 --> 00:05:00,600 alpha particle was just one anyhow or 10 179 00:05:00,600 --> 00:05:02,960 alpha particle was just one anyhow or 10 what any other so what what that simply 180 00:05:02,960 --> 00:05:02,970 what any other so what what that simply 181 00:05:02,970 --> 00:05:05,870 what any other so what what that simply means the beta particles that comes out 182 00:05:05,870 --> 00:05:05,880 means the beta particles that comes out 183 00:05:05,880 --> 00:05:08,090 means the beta particles that comes out from the nucleus does not stay in the 184 00:05:08,090 --> 00:05:08,100 from the nucleus does not stay in the 185 00:05:08,100 --> 00:05:11,540 from the nucleus does not stay in the outside of the nucleus and then becomes 186 00:05:11,540 --> 00:05:11,550 outside of the nucleus and then becomes 187 00:05:11,550 --> 00:05:14,510 outside of the nucleus and then becomes the electron of an atom no you can you 188 00:05:14,510 --> 00:05:14,520 the electron of an atom no you can you 189 00:05:14,520 --> 00:05:21,490 the electron of an atom no you can you can say that okay let's continue now 190 00:05:21,490 --> 00:05:21,500 can say that okay let's continue now 191 00:05:21,500 --> 00:05:25,610 can say that okay let's continue now alpha emission again there are no stable 192 00:05:25,610 --> 00:05:25,620 alpha emission again there are no stable 193 00:05:25,620 --> 00:05:27,560 alpha emission again there are no stable nuclei with an atomic number greater 194 00:05:27,560 --> 00:05:27,570 nuclei with an atomic number greater 195 00:05:27,570 --> 00:05:32,810 nuclei with an atomic number greater than 83 this is another things like all 196 00:05:32,810 --> 00:05:32,820 than 83 this is another things like all 197 00:05:32,820 --> 00:05:39,980 than 83 this is another things like all the atoms naturally occurring atoms in 198 00:05:39,980 --> 00:05:39,990 the atoms naturally occurring atoms in 199 00:05:39,990 --> 00:05:48,129 the atoms naturally occurring atoms in fact up to 83 now after 83 all the atoms 200 00:05:48,129 --> 00:05:48,139 fact up to 83 now after 83 all the atoms 201 00:05:48,139 --> 00:05:51,980 fact up to 83 now after 83 all the atoms are not simply stable they are all 202 00:05:51,980 --> 00:05:51,990 are not simply stable they are all 203 00:05:51,990 --> 00:05:56,150 are not simply stable they are all radioactive greater than 83 and nuclei 204 00:05:56,150 --> 00:05:56,160 radioactive greater than 83 and nuclei 205 00:05:56,160 --> 00:05:58,430 radioactive greater than 83 and nuclei with such large atomic numbers tend to 206 00:05:58,430 --> 00:05:58,440 with such large atomic numbers tend to 207 00:05:58,440 --> 00:06:00,290 with such large atomic numbers tend to decay by alpha emission they are not 208 00:06:00,290 --> 00:06:00,300 decay by alpha emission they are not 209 00:06:00,300 --> 00:06:02,930 decay by alpha emission they are not very stable actually most of those are 210 00:06:02,930 --> 00:06:02,940 very stable actually most of those are 211 00:06:02,940 --> 00:06:06,409 very stable actually most of those are made in the labs by nuclear reactions 212 00:06:06,409 --> 00:06:06,419 made in the labs by nuclear reactions 213 00:06:06,419 --> 00:06:08,779 made in the labs by nuclear reactions nuclear reactions and they are not 214 00:06:08,779 --> 00:06:08,789 nuclear reactions and they are not 215 00:06:08,789 --> 00:06:09,290 nuclear reactions and they are not stable 216 00:06:09,290 --> 00:06:09,300 stable 217 00:06:09,300 --> 00:06:11,510 stable they have half-lives we will talk about 218 00:06:11,510 --> 00:06:11,520 they have half-lives we will talk about 219 00:06:11,520 --> 00:06:14,600 they have half-lives we will talk about that certain time but they are not very 220 00:06:14,600 --> 00:06:14,610 that certain time but they are not very 221 00:06:14,610 --> 00:06:17,839 that certain time but they are not very stable so what happens if they are not 222 00:06:17,839 --> 00:06:17,849 stable so what happens if they are not 223 00:06:17,849 --> 00:06:18,800 stable so what happens if they are not stable they decay 224 00:06:18,800 --> 00:06:18,810 stable they decay 225 00:06:18,810 --> 00:06:21,530 stable they decay how by giving really large particles 226 00:06:21,530 --> 00:06:21,540 how by giving really large particles 227 00:06:21,540 --> 00:06:24,430 how by giving really large particles like beta particles as a matter of fact 228 00:06:24,430 --> 00:06:24,440 like beta particles as a matter of fact 229 00:06:24,440 --> 00:06:26,450 like beta particles as a matter of fact alpha particles excuse me alpha 230 00:06:26,450 --> 00:06:26,460 alpha particles excuse me alpha 231 00:06:26,460 --> 00:06:28,190 alpha particles excuse me alpha particles because the helium is large 232 00:06:28,190 --> 00:06:28,200 particles because the helium is large 233 00:06:28,200 --> 00:06:31,700 particles because the helium is large particles and they became by giving 234 00:06:31,700 --> 00:06:31,710 particles and they became by giving 235 00:06:31,710 --> 00:06:36,400 particles and they became by giving alpha emission actually alpha emission 236 00:06:36,400 --> 00:06:36,410 237 00:06:36,410 --> 00:06:45,290 now sometimes the decay process or the 238 00:06:45,290 --> 00:06:45,300 now sometimes the decay process or the 239 00:06:45,300 --> 00:06:48,470 now sometimes the decay process or the emission processes are not one step that 240 00:06:48,470 --> 00:06:48,480 emission processes are not one step that 241 00:06:48,480 --> 00:06:51,640 emission processes are not one step that means that an unstable radioactive 242 00:06:51,640 --> 00:06:51,650 means that an unstable radioactive 243 00:06:51,650 --> 00:06:56,270 means that an unstable radioactive nuclei cannot reach to a stable nuclide 244 00:06:56,270 --> 00:06:56,280 nuclei cannot reach to a stable nuclide 245 00:06:56,280 --> 00:06:59,750 nuclei cannot reach to a stable nuclide state by only one step so they may be 246 00:06:59,750 --> 00:06:59,760 state by only one step so they may be 247 00:06:59,760 --> 00:07:02,719 state by only one step so they may be more than one step radiations and 248 00:07:02,719 --> 00:07:02,729 more than one step radiations and 249 00:07:02,729 --> 00:07:04,430 more than one step radiations and nuclear reactions as a matter of fact as 250 00:07:04,430 --> 00:07:04,440 nuclear reactions as a matter of fact as 251 00:07:04,440 --> 00:07:12,159 nuclear reactions as a matter of fact as we see here for example uranium-235 252 00:07:12,159 --> 00:07:12,169 253 00:07:12,169 --> 00:07:15,190 uranium-238 I guess maybe in uranium 238 254 00:07:15,190 --> 00:07:15,200 uranium-238 I guess maybe in uranium 238 255 00:07:15,200 --> 00:07:19,040 uranium-238 I guess maybe in uranium 238 goes in alpha emissions and not only 256 00:07:19,040 --> 00:07:19,050 goes in alpha emissions and not only 257 00:07:19,050 --> 00:07:20,960 goes in alpha emissions and not only alpha emissions in fact in the same time 258 00:07:20,960 --> 00:07:20,970 alpha emissions in fact in the same time 259 00:07:20,970 --> 00:07:22,430 alpha emissions in fact in the same time it may give a beta emission gamma 260 00:07:22,430 --> 00:07:22,440 it may give a beta emission gamma 261 00:07:22,440 --> 00:07:24,740 it may give a beta emission gamma emissions in all others just the energy 262 00:07:24,740 --> 00:07:24,750 emissions in all others just the energy 263 00:07:24,750 --> 00:07:29,330 emissions in all others just the energy carries out and goes down from 238 264 00:07:29,330 --> 00:07:29,340 carries out and goes down from 238 265 00:07:29,340 --> 00:07:32,659 carries out and goes down from 238 atomic mass number 238 atomic number 92 266 00:07:32,659 --> 00:07:32,669 atomic mass number 238 atomic number 92 267 00:07:32,669 --> 00:07:37,420 atomic mass number 238 atomic number 92 and then decays in series each of these 268 00:07:37,420 --> 00:07:37,430 and then decays in series each of these 269 00:07:37,430 --> 00:07:41,000 and then decays in series each of these corresponds to a decay step and decay 270 00:07:41,000 --> 00:07:41,010 corresponds to a decay step and decay 271 00:07:41,010 --> 00:07:44,420 corresponds to a decay step and decay reaction and finally ends up to lead 272 00:07:44,420 --> 00:07:44,430 reaction and finally ends up to lead 273 00:07:44,430 --> 00:07:49,520 reaction and finally ends up to lead which is 208 or 206 mass number 207 and 274 00:07:49,520 --> 00:07:49,530 which is 208 or 206 mass number 207 and 275 00:07:49,530 --> 00:07:53,450 which is 208 or 206 mass number 207 and the atomic number of lead I guess is 82 276 00:07:53,450 --> 00:07:53,460 the atomic number of lead I guess is 82 277 00:07:53,460 --> 00:07:57,760 the atomic number of lead I guess is 82 as it's 82 there because that is the 278 00:07:57,760 --> 00:07:57,770 as it's 82 there because that is the 279 00:07:57,770 --> 00:08:01,159 as it's 82 there because that is the stable nuclei in fact stable nuclide so 280 00:08:01,159 --> 00:08:01,169 stable nuclei in fact stable nuclide so 281 00:08:01,169 --> 00:08:04,510 stable nuclei in fact stable nuclide so you see again some radioactive nucleus 282 00:08:04,510 --> 00:08:04,520 you see again some radioactive nucleus 283 00:08:04,520 --> 00:08:10,279 you see again some radioactive nucleus radioisotopes undergoes a chain nuclear 284 00:08:10,279 --> 00:08:10,289 radioisotopes undergoes a chain nuclear 285 00:08:10,289 --> 00:08:13,310 radioisotopes undergoes a chain nuclear reactions to reach to the most stable 286 00:08:13,310 --> 00:08:13,320 reactions to reach to the most stable 287 00:08:13,320 --> 00:08:20,659 reactions to reach to the most stable nuclei in that series again so let's see 288 00:08:20,659 --> 00:08:20,669 nuclei in that series again so let's see 289 00:08:20,669 --> 00:08:22,100 nuclei in that series again so let's see what it says here some radioactive 290 00:08:22,100 --> 00:08:22,110 what it says here some radioactive 291 00:08:22,110 --> 00:08:23,779 what it says here some radioactive nuclei cannot stabilize by undergoing 292 00:08:23,779 --> 00:08:23,789 nuclei cannot stabilize by undergoing 293 00:08:23,789 --> 00:08:25,129 nuclei cannot stabilize by undergoing only one nuclear transfer 294 00:08:25,129 --> 00:08:25,139 only one nuclear transfer 295 00:08:25,139 --> 00:08:27,589 only one nuclear transfer transformations they undergo a series of 296 00:08:27,589 --> 00:08:27,599 transformations they undergo a series of 297 00:08:27,599 --> 00:08:30,430 transformations they undergo a series of decays until they form a stable nuclei 298 00:08:30,430 --> 00:08:30,440 decays until they form a stable nuclei 299 00:08:30,440 --> 00:08:32,690 decays until they form a stable nuclei often a nucleoid of lad 300 00:08:32,690 --> 00:08:32,700 often a nucleoid of lad 301 00:08:32,700 --> 00:08:34,460 often a nucleoid of lad in this case you know the ladder is very 302 00:08:34,460 --> 00:08:34,470 in this case you know the ladder is very 303 00:08:34,470 --> 00:08:38,930 in this case you know the ladder is very stable as a matter of fact now the 304 00:08:38,930 --> 00:08:38,940 stable as a matter of fact now the 305 00:08:38,940 --> 00:08:42,710 stable as a matter of fact now the question here is why some nucleons are 306 00:08:42,710 --> 00:08:42,720 question here is why some nucleons are 307 00:08:42,720 --> 00:08:44,660 question here is why some nucleons are more stable than the others what is the 308 00:08:44,660 --> 00:08:44,670 more stable than the others what is the 309 00:08:44,670 --> 00:08:50,150 more stable than the others what is the reason now there are different ways of 310 00:08:50,150 --> 00:08:50,160 reason now there are different ways of 311 00:08:50,160 --> 00:08:52,970 reason now there are different ways of explaining that first of all they simply 312 00:08:52,970 --> 00:08:52,980 explaining that first of all they simply 313 00:08:52,980 --> 00:08:58,580 explaining that first of all they simply say that if a nuclei has even number of 314 00:08:58,580 --> 00:08:58,590 say that if a nuclei has even number of 315 00:08:58,590 --> 00:09:02,090 say that if a nuclei has even number of protons and even number of neutrons it 316 00:09:02,090 --> 00:09:02,100 protons and even number of neutrons it 317 00:09:02,100 --> 00:09:04,430 protons and even number of neutrons it is always more stable than the odd 318 00:09:04,430 --> 00:09:04,440 is always more stable than the odd 319 00:09:04,440 --> 00:09:07,220 is always more stable than the odd number of neat neutrons an odd number of 320 00:09:07,220 --> 00:09:07,230 number of neat neutrons an odd number of 321 00:09:07,230 --> 00:09:09,080 number of neat neutrons an odd number of protons as a matter of fact so that's 322 00:09:09,080 --> 00:09:09,090 protons as a matter of fact so that's 323 00:09:09,090 --> 00:09:11,360 protons as a matter of fact so that's again important now in addition to that 324 00:09:11,360 --> 00:09:11,370 again important now in addition to that 325 00:09:11,370 --> 00:09:16,820 again important now in addition to that they simply say that if a nuclei has 2 8 326 00:09:16,820 --> 00:09:16,830 they simply say that if a nuclei has 2 8 327 00:09:16,830 --> 00:09:21,560 they simply say that if a nuclei has 2 8 20 28 50 82 protons and it has like 2 8 328 00:09:21,560 --> 00:09:21,570 20 28 50 82 protons and it has like 2 8 329 00:09:21,570 --> 00:09:26,180 20 28 50 82 protons and it has like 2 8 20 28 50 82 and 126 neutrons they are 330 00:09:26,180 --> 00:09:26,190 20 28 50 82 and 126 neutrons they are 331 00:09:26,190 --> 00:09:28,970 20 28 50 82 and 126 neutrons they are more stable why they are simply called 332 00:09:28,970 --> 00:09:28,980 more stable why they are simply called 333 00:09:28,980 --> 00:09:32,030 more stable why they are simply called magic numbers actually you can probably 334 00:09:32,030 --> 00:09:32,040 magic numbers actually you can probably 335 00:09:32,040 --> 00:09:35,720 magic numbers actually you can probably visualize this or associated with the in 336 00:09:35,720 --> 00:09:35,730 visualize this or associated with the in 337 00:09:35,730 --> 00:09:38,030 visualize this or associated with the in a chronic structure of the atoms 338 00:09:38,030 --> 00:09:38,040 a chronic structure of the atoms 339 00:09:38,040 --> 00:09:42,770 a chronic structure of the atoms remember when the atom electrons 340 00:09:42,770 --> 00:09:42,780 remember when the atom electrons 341 00:09:42,780 --> 00:09:44,750 remember when the atom electrons structure is the same as the noble gas 342 00:09:44,750 --> 00:09:44,760 structure is the same as the noble gas 343 00:09:44,760 --> 00:09:46,970 structure is the same as the noble gas electron structure which means closed 344 00:09:46,970 --> 00:09:46,980 electron structure which means closed 345 00:09:46,980 --> 00:09:48,620 electron structure which means closed shell electrons structure they are more 346 00:09:48,620 --> 00:09:48,630 shell electrons structure they are more 347 00:09:48,630 --> 00:09:53,360 shell electrons structure they are more stable right all of the noble gases in 348 00:09:53,360 --> 00:09:53,370 stable right all of the noble gases in 349 00:09:53,370 --> 00:09:56,000 stable right all of the noble gases in fact very inert they are not reacting 350 00:09:56,000 --> 00:09:56,010 fact very inert they are not reacting 351 00:09:56,010 --> 00:10:00,290 fact very inert they are not reacting very stable and in this case the nuclei 352 00:10:00,290 --> 00:10:00,300 very stable and in this case the nuclei 353 00:10:00,300 --> 00:10:03,230 very stable and in this case the nuclei that have these number of protons and 354 00:10:03,230 --> 00:10:03,240 that have these number of protons and 355 00:10:03,240 --> 00:10:06,620 that have these number of protons and neutrons are more stable and they simply 356 00:10:06,620 --> 00:10:06,630 neutrons are more stable and they simply 357 00:10:06,630 --> 00:10:08,750 neutrons are more stable and they simply call these numbers called magic numbers 358 00:10:08,750 --> 00:10:08,760 call these numbers called magic numbers 359 00:10:08,760 --> 00:10:11,180 call these numbers called magic numbers again nuclei with an even number of 360 00:10:11,180 --> 00:10:11,190 again nuclei with an even number of 361 00:10:11,190 --> 00:10:13,370 again nuclei with an even number of protons and neutrons tend to be more 362 00:10:13,370 --> 00:10:13,380 protons and neutrons tend to be more 363 00:10:13,380 --> 00:10:15,740 protons and neutrons tend to be more stable than those with odd numbers as I 364 00:10:15,740 --> 00:10:15,750 stable than those with odd numbers as I 365 00:10:15,750 --> 00:10:20,870 stable than those with odd numbers as I said and here we look at the number of 366 00:10:20,870 --> 00:10:20,880 said and here we look at the number of 367 00:10:20,880 --> 00:10:26,150 said and here we look at the number of stable isotopes of one isotopes with 368 00:10:26,150 --> 00:10:26,160 stable isotopes of one isotopes with 369 00:10:26,160 --> 00:10:31,280 stable isotopes of one isotopes with even and even 157 isotopes are stable 370 00:10:31,280 --> 00:10:31,290 even and even 157 isotopes are stable 371 00:10:31,290 --> 00:10:34,400 even and even 157 isotopes are stable and all of those 157 isotopes has even 372 00:10:34,400 --> 00:10:34,410 and all of those 157 isotopes has even 373 00:10:34,410 --> 00:10:36,680 and all of those 157 isotopes has even number of proton even number of neutrons 374 00:10:36,680 --> 00:10:36,690 number of proton even number of neutrons 375 00:10:36,690 --> 00:10:40,700 number of proton even number of neutrons now there are 53 stable isotopes with 376 00:10:40,700 --> 00:10:40,710 now there are 53 stable isotopes with 377 00:10:40,710 --> 00:10:42,830 now there are 53 stable isotopes with even number of protons and odd number of 378 00:10:42,830 --> 00:10:42,840 even number of protons and odd number of 379 00:10:42,840 --> 00:10:45,680 even number of protons and odd number of neutrons and there are only five ice 380 00:10:45,680 --> 00:10:45,690 neutrons and there are only five ice 381 00:10:45,690 --> 00:10:48,680 neutrons and there are only five ice Taub's which is which are stable and 382 00:10:48,680 --> 00:10:48,690 Taub's which is which are stable and 383 00:10:48,690 --> 00:10:52,760 Taub's which is which are stable and they have actually odd number of protons 384 00:10:52,760 --> 00:10:52,770 they have actually odd number of protons 385 00:10:52,770 --> 00:10:54,560 they have actually odd number of protons and odd number of neutrons again you see 386 00:10:54,560 --> 00:10:54,570 and odd number of neutrons again you see 387 00:10:54,570 --> 00:10:58,160 and odd number of neutrons again you see the oddness of the number of protons and 388 00:10:58,160 --> 00:10:58,170 the oddness of the number of protons and 389 00:10:58,170 --> 00:10:59,810 the oddness of the number of protons and the number of neutrons becomes a very 390 00:10:59,810 --> 00:10:59,820 the number of neutrons becomes a very 391 00:10:59,820 --> 00:11:03,020 the number of neutrons becomes a very important factor in determining the 392 00:11:03,020 --> 00:11:03,030 important factor in determining the 393 00:11:03,030 --> 00:11:05,990 important factor in determining the stability of the nuclei is actually the 394 00:11:05,990 --> 00:11:06,000 stability of the nuclei is actually the 395 00:11:06,000 --> 00:11:09,530 stability of the nuclei is actually the nucleus as a matter of fact now these 396 00:11:09,530 --> 00:11:09,540 nucleus as a matter of fact now these 397 00:11:09,540 --> 00:11:12,650 nucleus as a matter of fact now these simply gives you the elements with the 398 00:11:12,650 --> 00:11:12,660 simply gives you the elements with the 399 00:11:12,660 --> 00:11:16,040 simply gives you the elements with the number of stable isotopes and again all 400 00:11:16,040 --> 00:11:16,050 number of stable isotopes and again all 401 00:11:16,050 --> 00:11:19,160 number of stable isotopes and again all of the elements which have even number 402 00:11:19,160 --> 00:11:19,170 of the elements which have even number 403 00:11:19,170 --> 00:11:21,860 of the elements which have even number of protons always has more stable 404 00:11:21,860 --> 00:11:21,870 of protons always has more stable 405 00:11:21,870 --> 00:11:24,890 of protons always has more stable isotopes with the one with odd number of 406 00:11:24,890 --> 00:11:24,900 isotopes with the one with odd number of 407 00:11:24,900 --> 00:11:27,740 isotopes with the one with odd number of protons again these are odd number this 408 00:11:27,740 --> 00:11:27,750 protons again these are odd number this 409 00:11:27,750 --> 00:11:30,500 protons again these are odd number this is even odd even odd and that gives you 410 00:11:30,500 --> 00:11:30,510 is even odd even odd and that gives you 411 00:11:30,510 --> 00:11:33,560 is even odd even odd and that gives you the number of stable nuclei stable 412 00:11:33,560 --> 00:11:33,570 the number of stable nuclei stable 413 00:11:33,570 --> 00:11:37,160 the number of stable nuclei stable nucleus again try to show you that 414 00:11:37,160 --> 00:11:37,170 nucleus again try to show you that 415 00:11:37,170 --> 00:11:40,700 nucleus again try to show you that somehow even number of protons and even 416 00:11:40,700 --> 00:11:40,710 somehow even number of protons and even 417 00:11:40,710 --> 00:11:46,060 somehow even number of protons and even number of neutrons yields a more stable 418 00:11:46,060 --> 00:11:46,070 number of neutrons yields a more stable 419 00:11:46,070 --> 00:11:50,590 number of neutrons yields a more stable nucleus again no more stable nuclides 420 00:11:50,590 --> 00:11:50,600 nucleus again no more stable nuclides 421 00:11:50,600 --> 00:11:54,680 nucleus again no more stable nuclides now so far we have simply talked about 422 00:11:54,680 --> 00:11:54,690 now so far we have simply talked about 423 00:11:54,690 --> 00:12:01,880 now so far we have simply talked about the decay of n decline right that means 424 00:12:01,880 --> 00:12:01,890 the decay of n decline right that means 425 00:12:01,890 --> 00:12:04,010 the decay of n decline right that means like a unimolecular reaction it 426 00:12:04,010 --> 00:12:04,020 like a unimolecular reaction it 427 00:12:04,020 --> 00:12:08,000 like a unimolecular reaction it decomposes it emits particles or you 428 00:12:08,000 --> 00:12:08,010 decomposes it emits particles or you 429 00:12:08,010 --> 00:12:11,480 decomposes it emits particles or you know and goes to a lower energy more 430 00:12:11,480 --> 00:12:11,490 know and goes to a lower energy more 431 00:12:11,490 --> 00:12:14,960 know and goes to a lower energy more stable state but it is also possible 432 00:12:14,960 --> 00:12:14,970 stable state but it is also possible 433 00:12:14,970 --> 00:12:20,440 stable state but it is also possible that when you simply strike a nuclei 434 00:12:20,440 --> 00:12:20,450 that when you simply strike a nuclei 435 00:12:20,450 --> 00:12:26,330 that when you simply strike a nuclei with another smaller light nucleons you 436 00:12:26,330 --> 00:12:26,340 with another smaller light nucleons you 437 00:12:26,340 --> 00:12:29,690 with another smaller light nucleons you may have a nuclear reactions nuclear 438 00:12:29,690 --> 00:12:29,700 may have a nuclear reactions nuclear 439 00:12:29,700 --> 00:12:32,420 may have a nuclear reactions nuclear reactions now as a result of this new 440 00:12:32,420 --> 00:12:32,430 reactions now as a result of this new 441 00:12:32,430 --> 00:12:34,540 reactions now as a result of this new nuclear these type of nuclear reactions 442 00:12:34,540 --> 00:12:34,550 nuclear these type of nuclear reactions 443 00:12:34,550 --> 00:12:38,230 nuclear these type of nuclear reactions always an element identity is changed 444 00:12:38,230 --> 00:12:38,240 always an element identity is changed 445 00:12:38,240 --> 00:12:41,240 always an element identity is changed that mean is not the same elements that 446 00:12:41,240 --> 00:12:41,250 that mean is not the same elements that 447 00:12:41,250 --> 00:12:43,100 that mean is not the same elements that we have at the beginning and that's why 448 00:12:43,100 --> 00:12:43,110 we have at the beginning and that's why 449 00:12:43,110 --> 00:12:46,490 we have at the beginning and that's why these type of nuclear reactions are 450 00:12:46,490 --> 00:12:46,500 these type of nuclear reactions are 451 00:12:46,500 --> 00:12:49,790 these type of nuclear reactions are called nuclear transmutations that means 452 00:12:49,790 --> 00:12:49,800 called nuclear transmutations that means 453 00:12:49,800 --> 00:12:52,910 called nuclear transmutations that means the chemical identity identity of the 454 00:12:52,910 --> 00:12:52,920 the chemical identity identity of the 455 00:12:52,920 --> 00:12:55,640 the chemical identity identity of the atom changes as a matter of fact so 456 00:12:55,640 --> 00:12:55,650 atom changes as a matter of fact so 457 00:12:55,650 --> 00:12:57,680 atom changes as a matter of fact so let's look at how we describe nuclear 458 00:12:57,680 --> 00:12:57,690 let's look at how we describe nuclear 459 00:12:57,690 --> 00:12:59,330 let's look at how we describe nuclear transportations can be in 460 00:12:59,330 --> 00:12:59,340 transportations can be in 461 00:12:59,340 --> 00:13:02,570 transportations can be in Jews by accelerating particle two 462 00:13:02,570 --> 00:13:02,580 Jews by accelerating particle two 463 00:13:02,580 --> 00:13:05,480 Jews by accelerating particle two collided with the nuclide you simply 464 00:13:05,480 --> 00:13:05,490 collided with the nuclide you simply 465 00:13:05,490 --> 00:13:07,700 collided with the nuclide you simply have an accelerate and very accelerating 466 00:13:07,700 --> 00:13:07,710 have an accelerate and very accelerating 467 00:13:07,710 --> 00:13:09,500 have an accelerate and very accelerating particle miss simply means high energy 468 00:13:09,500 --> 00:13:09,510 particle miss simply means high energy 469 00:13:09,510 --> 00:13:11,420 particle miss simply means high energy particle has kinetic energy very large 470 00:13:11,420 --> 00:13:11,430 particle has kinetic energy very large 471 00:13:11,430 --> 00:13:14,930 particle has kinetic energy very large kinetic energy so remember again usually 472 00:13:14,930 --> 00:13:14,940 kinetic energy so remember again usually 473 00:13:14,940 --> 00:13:18,350 kinetic energy so remember again usually these particles are charged particles to 474 00:13:18,350 --> 00:13:18,360 these particles are charged particles to 475 00:13:18,360 --> 00:13:21,590 these particles are charged particles to be able to accelerate a particle it has 476 00:13:21,590 --> 00:13:21,600 be able to accelerate a particle it has 477 00:13:21,600 --> 00:13:24,019 be able to accelerate a particle it has to be charged and usually positively 478 00:13:24,019 --> 00:13:24,029 to be charged and usually positively 479 00:13:24,029 --> 00:13:26,210 to be charged and usually positively charged particles like a proton or like 480 00:13:26,210 --> 00:13:26,220 charged particles like a proton or like 481 00:13:26,220 --> 00:13:29,630 charged particles like a proton or like an alpha particles now the nucleus the 482 00:13:29,630 --> 00:13:29,640 an alpha particles now the nucleus the 483 00:13:29,640 --> 00:13:31,940 an alpha particles now the nucleus the nucleus is also a positively charged so 484 00:13:31,940 --> 00:13:31,950 nucleus is also a positively charged so 485 00:13:31,950 --> 00:13:35,870 nucleus is also a positively charged so to have two particles with both 486 00:13:35,870 --> 00:13:35,880 to have two particles with both 487 00:13:35,880 --> 00:13:38,660 to have two particles with both positively charged which they repel each 488 00:13:38,660 --> 00:13:38,670 positively charged which they repel each 489 00:13:38,670 --> 00:13:40,850 positively charged which they repel each other they should have a very large 490 00:13:40,850 --> 00:13:40,860 other they should have a very large 491 00:13:40,860 --> 00:13:42,769 other they should have a very large amount of energy that they will strike 492 00:13:42,769 --> 00:13:42,779 amount of energy that they will strike 493 00:13:42,779 --> 00:13:45,590 amount of energy that they will strike each other right so therefore usually 494 00:13:45,590 --> 00:13:45,600 each other right so therefore usually 495 00:13:45,600 --> 00:13:49,030 each other right so therefore usually the smaller particle charged particle is 496 00:13:49,030 --> 00:13:49,040 the smaller particle charged particle is 497 00:13:49,040 --> 00:13:51,560 the smaller particle charged particle is accelerated now the speed of that 498 00:13:51,560 --> 00:13:51,570 accelerated now the speed of that 499 00:13:51,570 --> 00:13:54,050 accelerated now the speed of that increased increase actually it is 500 00:13:54,050 --> 00:13:54,060 increased increase actually it is 501 00:13:54,060 --> 00:13:57,829 increased increase actually it is increased almost nine ninety seven 502 00:13:57,829 --> 00:13:57,839 increased almost nine ninety seven 503 00:13:57,839 --> 00:13:59,750 increased almost nine ninety seven percent of the speed of light 504 00:13:59,750 --> 00:13:59,760 percent of the speed of light 505 00:13:59,760 --> 00:14:03,200 percent of the speed of light can you imagine very very high speed you 506 00:14:03,200 --> 00:14:03,210 can you imagine very very high speed you 507 00:14:03,210 --> 00:14:05,420 can you imagine very very high speed you can increase the speed of a proton by 508 00:14:05,420 --> 00:14:05,430 can increase the speed of a proton by 509 00:14:05,430 --> 00:14:07,600 can increase the speed of a proton by the accelerators as we will show you 510 00:14:07,600 --> 00:14:07,610 the accelerators as we will show you 511 00:14:07,610 --> 00:14:11,300 the accelerators as we will show you very close to or let's not say close to 512 00:14:11,300 --> 00:14:11,310 very close to or let's not say close to 513 00:14:11,310 --> 00:14:15,820 very close to or let's not say close to if you consider that 97 percent of the 514 00:14:15,820 --> 00:14:15,830 if you consider that 97 percent of the 515 00:14:15,830 --> 00:14:18,710 if you consider that 97 percent of the speed of light is close to the speed of 516 00:14:18,710 --> 00:14:18,720 speed of light is close to the speed of 517 00:14:18,720 --> 00:14:21,470 speed of light is close to the speed of light so they increase the energies of 518 00:14:21,470 --> 00:14:21,480 light so they increase the energies of 519 00:14:21,480 --> 00:14:23,829 light so they increase the energies of that and then when it strikes another 520 00:14:23,829 --> 00:14:23,839 that and then when it strikes another 521 00:14:23,839 --> 00:14:27,560 that and then when it strikes another nuclides then this transmutation 522 00:14:27,560 --> 00:14:27,570 nuclides then this transmutation 523 00:14:27,570 --> 00:14:28,840 nuclides then this transmutation reaction is taking place 524 00:14:28,840 --> 00:14:28,850 reaction is taking place 525 00:14:28,850 --> 00:14:30,940 reaction is taking place transportation reaction is taking place 526 00:14:30,940 --> 00:14:30,950 transportation reaction is taking place 527 00:14:30,950 --> 00:14:34,820 transportation reaction is taking place so the particle accelerators they are 528 00:14:34,820 --> 00:14:34,830 so the particle accelerators they are 529 00:14:34,830 --> 00:14:36,860 so the particle accelerators they are called atoms smashers that means we 530 00:14:36,860 --> 00:14:36,870 called atoms smashers that means we 531 00:14:36,870 --> 00:14:38,360 called atoms smashers that means we accelerate the particle accelerator 532 00:14:38,360 --> 00:14:38,370 accelerate the particle accelerator 533 00:14:38,370 --> 00:14:40,760 accelerate the particle accelerator accelerate accelerate then hit it to a 534 00:14:40,760 --> 00:14:40,770 accelerate accelerate then hit it to a 535 00:14:40,770 --> 00:14:43,730 accelerate accelerate then hit it to a nucleus right now think about this is a 536 00:14:43,730 --> 00:14:43,740 nucleus right now think about this is a 537 00:14:43,740 --> 00:14:46,370 nucleus right now think about this is a nucleus not the atom but the nucleus 538 00:14:46,370 --> 00:14:46,380 nucleus not the atom but the nucleus 539 00:14:46,380 --> 00:14:48,320 nucleus not the atom but the nucleus they have to hit to the nucleus in fact 540 00:14:48,320 --> 00:14:48,330 they have to hit to the nucleus in fact 541 00:14:48,330 --> 00:14:51,980 they have to hit to the nucleus in fact and we have the enormous seven circular 542 00:14:51,980 --> 00:14:51,990 and we have the enormous seven circular 543 00:14:51,990 --> 00:14:54,199 and we have the enormous seven circular tracks with radii that are miles along 544 00:14:54,199 --> 00:14:54,209 tracks with radii that are miles along 545 00:14:54,209 --> 00:14:56,240 tracks with radii that are miles along the particle accelerators to increase 546 00:14:56,240 --> 00:14:56,250 the particle accelerators to increase 547 00:14:56,250 --> 00:14:59,360 the particle accelerators to increase that we use actually these accelerators 548 00:14:59,360 --> 00:14:59,370 that we use actually these accelerators 549 00:14:59,370 --> 00:15:03,769 that we use actually these accelerators are used I guess this one is I can't 550 00:15:03,769 --> 00:15:03,779 are used I guess this one is I can't 551 00:15:03,779 --> 00:15:06,320 are used I guess this one is I can't remember but about 10 kilometers 552 00:15:06,320 --> 00:15:06,330 remember but about 10 kilometers 553 00:15:06,330 --> 00:15:09,010 remember but about 10 kilometers somewhere about seven kilometers 554 00:15:09,010 --> 00:15:09,020 somewhere about seven kilometers 555 00:15:09,020 --> 00:15:12,320 somewhere about seven kilometers circumference and here we have a 556 00:15:12,320 --> 00:15:12,330 circumference and here we have a 557 00:15:12,330 --> 00:15:13,100 circumference and here we have a magnetic view 558 00:15:13,100 --> 00:15:13,110 magnetic view 559 00:15:13,110 --> 00:15:14,930 magnetic view electric field and charged particle 560 00:15:14,930 --> 00:15:14,940 electric field and charged particle 561 00:15:14,940 --> 00:15:17,210 electric field and charged particle enter to this and they go up here in the 562 00:15:17,210 --> 00:15:17,220 enter to this and they go up here in the 563 00:15:17,220 --> 00:15:19,010 enter to this and they go up here in the electrical field that merrily increases 564 00:15:19,010 --> 00:15:19,020 electrical field that merrily increases 565 00:15:19,020 --> 00:15:21,020 electrical field that merrily increases the kinetic energy increase in the 566 00:15:21,020 --> 00:15:21,030 the kinetic energy increase in the 567 00:15:21,030 --> 00:15:22,370 the kinetic energy increase in the kinetic energy kinetic energy and 568 00:15:22,370 --> 00:15:22,380 kinetic energy kinetic energy and 569 00:15:22,380 --> 00:15:24,670 kinetic energy kinetic energy and finally we get it out and hit it to 570 00:15:24,670 --> 00:15:24,680 finally we get it out and hit it to 571 00:15:24,680 --> 00:15:27,320 finally we get it out and hit it to another nucleus right this is how the 572 00:15:27,320 --> 00:15:27,330 another nucleus right this is how the 573 00:15:27,330 --> 00:15:29,420 another nucleus right this is how the transmutation reactions are simply 574 00:15:29,420 --> 00:15:29,430 transmutation reactions are simply 575 00:15:29,430 --> 00:15:32,330 transmutation reactions are simply taking place and there is an accelerator 576 00:15:32,330 --> 00:15:32,340 taking place and there is an accelerator 577 00:15:32,340 --> 00:15:36,050 taking place and there is an accelerator in New York and there is an accelerator 578 00:15:36,050 --> 00:15:36,060 in New York and there is an accelerator 579 00:15:36,060 --> 00:15:39,410 in New York and there is an accelerator in Chicago and in the states and there 580 00:15:39,410 --> 00:15:39,420 in Chicago and in the states and there 581 00:15:39,420 --> 00:15:40,100 in Chicago and in the states and there is also one 582 00:15:40,100 --> 00:15:40,110 is also one 583 00:15:40,110 --> 00:15:44,030 is also one accelerator in Geneva CERN and that is 584 00:15:44,030 --> 00:15:44,040 accelerator in Geneva CERN and that is 585 00:15:44,040 --> 00:15:45,860 accelerator in Geneva CERN and that is used by all the European country 586 00:15:45,860 --> 00:15:45,870 used by all the European country 587 00:15:45,870 --> 00:15:48,830 used by all the European country scientists in fact there not much of 588 00:15:48,830 --> 00:15:48,840 scientists in fact there not much of 589 00:15:48,840 --> 00:15:50,660 scientists in fact there not much of those are very expensive actually and 590 00:15:50,660 --> 00:15:50,670 those are very expensive actually and 591 00:15:50,670 --> 00:15:53,170 those are very expensive actually and they built them up underground 592 00:15:53,170 --> 00:15:53,180 they built them up underground 593 00:15:53,180 --> 00:15:56,300 they built them up underground everything is underground again right 594 00:15:56,300 --> 00:15:56,310 everything is underground again right 595 00:15:56,310 --> 00:15:58,490 everything is underground again right and you carry out the reactions you 596 00:15:58,490 --> 00:15:58,500 and you carry out the reactions you 597 00:15:58,500 --> 00:16:01,340 and you carry out the reactions you smash the high-energy particles small 598 00:16:01,340 --> 00:16:01,350 smash the high-energy particles small 599 00:16:01,350 --> 00:16:04,010 smash the high-energy particles small particles and then you watch and follow 600 00:16:04,010 --> 00:16:04,020 particles and then you watch and follow 601 00:16:04,020 --> 00:16:06,110 particles and then you watch and follow what products will come on what kind of 602 00:16:06,110 --> 00:16:06,120 what products will come on what kind of 603 00:16:06,120 --> 00:16:08,110 what products will come on what kind of reactions and these are actually all 604 00:16:08,110 --> 00:16:08,120 reactions and these are actually all 605 00:16:08,120 --> 00:16:10,790 reactions and these are actually all chemical reactions remember the boson 606 00:16:10,790 --> 00:16:10,800 chemical reactions remember the boson 607 00:16:10,800 --> 00:16:12,980 chemical reactions remember the boson experiment was also carried out in CERN 608 00:16:12,980 --> 00:16:12,990 experiment was also carried out in CERN 609 00:16:12,990 --> 00:16:22,780 experiment was also carried out in CERN in Geneva right there now other nuclear 610 00:16:22,780 --> 00:16:22,790 in Geneva right there now other nuclear 611 00:16:22,790 --> 00:16:25,370 in Geneva right there now other nuclear transmutation nuclear generation use of 612 00:16:25,370 --> 00:16:25,380 transmutation nuclear generation use of 613 00:16:25,380 --> 00:16:29,200 transmutation nuclear generation use of neutrons again now those that are 614 00:16:29,200 --> 00:16:29,210 neutrons again now those that are 615 00:16:29,210 --> 00:16:32,030 neutrons again now those that are accelerated are charged particles you 616 00:16:32,030 --> 00:16:32,040 accelerated are charged particles you 617 00:16:32,040 --> 00:16:33,710 accelerated are charged particles you can't really accelerate the neutrons 618 00:16:33,710 --> 00:16:33,720 can't really accelerate the neutrons 619 00:16:33,720 --> 00:16:35,990 can't really accelerate the neutrons there right because it doesn't have a 620 00:16:35,990 --> 00:16:36,000 there right because it doesn't have a 621 00:16:36,000 --> 00:16:40,390 there right because it doesn't have a charge but you can use it neutrons from 622 00:16:40,390 --> 00:16:40,400 charge but you can use it neutrons from 623 00:16:40,400 --> 00:16:42,830 charge but you can use it neutrons from nuclear reactions actually that comes 624 00:16:42,830 --> 00:16:42,840 nuclear reactions actually that comes 625 00:16:42,840 --> 00:16:46,160 nuclear reactions actually that comes out from the atom and use that Neutron 626 00:16:46,160 --> 00:16:46,170 out from the atom and use that Neutron 627 00:16:46,170 --> 00:16:48,410 out from the atom and use that Neutron and carry out the transportation 628 00:16:48,410 --> 00:16:48,420 and carry out the transportation 629 00:16:48,420 --> 00:16:51,080 and carry out the transportation reactions and here again says most 630 00:16:51,080 --> 00:16:51,090 reactions and here again says most 631 00:16:51,090 --> 00:16:53,570 reactions and here again says most synthetic isotopes used in medicine are 632 00:16:53,570 --> 00:16:53,580 synthetic isotopes used in medicine are 633 00:16:53,580 --> 00:16:56,750 synthetic isotopes used in medicine are prepared by bombarding neutrons at a 634 00:16:56,750 --> 00:16:56,760 prepared by bombarding neutrons at a 635 00:16:56,760 --> 00:16:59,300 prepared by bombarding neutrons at a particle which won't repel the neutron 636 00:16:59,300 --> 00:16:59,310 particle which won't repel the neutron 637 00:16:59,310 --> 00:17:07,880 particle which won't repel the neutron particles actually in nuclear reactors 638 00:17:07,880 --> 00:17:07,890 particles actually in nuclear reactors 639 00:17:07,890 --> 00:17:09,439 particles actually in nuclear reactors actually if you have a nuclear reactors 640 00:17:09,439 --> 00:17:09,449 actually if you have a nuclear reactors 641 00:17:09,449 --> 00:17:13,870 actually if you have a nuclear reactors and if you have a proton given nuclear 642 00:17:13,870 --> 00:17:13,880 and if you have a proton given nuclear 643 00:17:13,880 --> 00:17:15,890 and if you have a proton given nuclear radioactive reactions the nuclear 644 00:17:15,890 --> 00:17:15,900 radioactive reactions the nuclear 645 00:17:15,900 --> 00:17:18,410 radioactive reactions the nuclear reactions you can take those protons and 646 00:17:18,410 --> 00:17:18,420 reactions you can take those protons and 647 00:17:18,420 --> 00:17:21,620 reactions you can take those protons and then collided with other atoms 648 00:17:21,620 --> 00:17:21,630 then collided with other atoms 649 00:17:21,630 --> 00:17:24,740 then collided with other atoms since the neutron it says has neutral 650 00:17:24,740 --> 00:17:24,750 since the neutron it says has neutral 651 00:17:24,750 --> 00:17:26,569 since the neutron it says has neutral charge it doesn't need to 652 00:17:26,569 --> 00:17:26,579 charge it doesn't need to 653 00:17:26,579 --> 00:17:28,909 charge it doesn't need to large energy to hit the positively 654 00:17:28,909 --> 00:17:28,919 large energy to hit the positively 655 00:17:28,919 --> 00:17:31,610 large energy to hit the positively charged nucleus actually right nuclei 656 00:17:31,610 --> 00:17:31,620 charged nucleus actually right nuclei 657 00:17:31,620 --> 00:17:35,539 charged nucleus actually right nuclei and for example cobalt-60 which is used 658 00:17:35,539 --> 00:17:35,549 and for example cobalt-60 which is used 659 00:17:35,549 --> 00:17:41,600 and for example cobalt-60 which is used in in hospitals in in in nikiro of 660 00:17:41,600 --> 00:17:41,610 in in hospitals in in in nikiro of 661 00:17:41,610 --> 00:17:46,130 in in hospitals in in in nikiro of cancers and radio therapies are prepared 662 00:17:46,130 --> 00:17:46,140 cancers and radio therapies are prepared 663 00:17:46,140 --> 00:17:49,610 cancers and radio therapies are prepared by bombarding the iron 57 by the 664 00:17:49,610 --> 00:17:49,620 by bombarding the iron 57 by the 665 00:17:49,620 --> 00:17:51,769 by bombarding the iron 57 by the neutrons in fact and in two or three 666 00:17:51,769 --> 00:17:51,779 neutrons in fact and in two or three 667 00:17:51,779 --> 00:17:53,810 neutrons in fact and in two or three steps you get cobalt 50 which is a 668 00:17:53,810 --> 00:17:53,820 steps you get cobalt 50 which is a 669 00:17:53,820 --> 00:17:55,789 steps you get cobalt 50 which is a radioactive cobalt 60 which is a 670 00:17:55,789 --> 00:17:55,799 radioactive cobalt 60 which is a 671 00:17:55,799 --> 00:18:00,159 radioactive cobalt 60 which is a radioactive that's how its prepared now 672 00:18:00,159 --> 00:18:00,169 radioactive that's how its prepared now 673 00:18:00,169 --> 00:18:02,750 radioactive that's how its prepared now transuranium elements when we say 674 00:18:02,750 --> 00:18:02,760 transuranium elements when we say 675 00:18:02,760 --> 00:18:04,129 transuranium elements when we say transuranium elements these are the 676 00:18:04,129 --> 00:18:04,139 transuranium elements these are the 677 00:18:04,139 --> 00:18:07,129 transuranium elements these are the elements that have greater atomic number 678 00:18:07,129 --> 00:18:07,139 elements that have greater atomic number 679 00:18:07,139 --> 00:18:10,250 elements that have greater atomic number than uranium which is 92 remember all of 680 00:18:10,250 --> 00:18:10,260 than uranium which is 92 remember all of 681 00:18:10,260 --> 00:18:13,009 than uranium which is 92 remember all of those are not stable and all of those 682 00:18:13,009 --> 00:18:13,019 those are not stable and all of those 683 00:18:13,019 --> 00:18:14,930 those are not stable and all of those are prepared in the lab elements 684 00:18:14,930 --> 00:18:14,940 are prepared in the lab elements 685 00:18:14,940 --> 00:18:16,549 are prepared in the lab elements immediately after the uranium were 686 00:18:16,549 --> 00:18:16,559 immediately after the uranium were 687 00:18:16,559 --> 00:18:20,269 immediately after the uranium were discovered by bombarding isotopes with 688 00:18:20,269 --> 00:18:20,279 discovered by bombarding isotopes with 689 00:18:20,279 --> 00:18:23,659 discovered by bombarding isotopes with neutrons you see we just bombard them 690 00:18:23,659 --> 00:18:23,669 neutrons you see we just bombard them 691 00:18:23,669 --> 00:18:26,480 neutrons you see we just bombard them with neutrons large elements atomic 692 00:18:26,480 --> 00:18:26,490 with neutrons large elements atomic 693 00:18:26,490 --> 00:18:28,700 with neutrons large elements atomic number higher than hundred and ten were 694 00:18:28,700 --> 00:18:28,710 number higher than hundred and ten were 695 00:18:28,710 --> 00:18:31,279 number higher than hundred and ten were made by colliding large atoms with 696 00:18:31,279 --> 00:18:31,289 made by colliding large atoms with 697 00:18:31,289 --> 00:18:33,649 made by colliding large atoms with nuclei of white elements with high 698 00:18:33,649 --> 00:18:33,659 nuclei of white elements with high 699 00:18:33,659 --> 00:18:35,810 nuclei of white elements with high energy this is again from those 700 00:18:35,810 --> 00:18:35,820 energy this is again from those 701 00:18:35,820 --> 00:18:37,909 energy this is again from those accelerators lots such as alpha 702 00:18:37,909 --> 00:18:37,919 accelerators lots such as alpha 703 00:18:37,919 --> 00:18:40,519 accelerators lots such as alpha particles you accelerate those and hit 704 00:18:40,519 --> 00:18:40,529 particles you accelerate those and hit 705 00:18:40,529 --> 00:18:47,060 particles you accelerate those and hit it to another nucleons now right in the 706 00:18:47,060 --> 00:18:47,070 it to another nucleons now right in the 707 00:18:47,070 --> 00:18:49,810 it to another nucleons now right in the nuclear equations for nuclear 708 00:18:49,810 --> 00:18:49,820 nuclear equations for nuclear 709 00:18:49,820 --> 00:18:52,460 nuclear equations for nuclear transmutations again these nuclear 710 00:18:52,460 --> 00:18:52,470 transmutations again these nuclear 711 00:18:52,470 --> 00:18:57,049 transmutations again these nuclear transmutations is a nuclear reactions 712 00:18:57,049 --> 00:18:57,059 transmutations is a nuclear reactions 713 00:18:57,059 --> 00:19:00,110 transmutations is a nuclear reactions though they will have a nuclear reaction 714 00:19:00,110 --> 00:19:00,120 though they will have a nuclear reaction 715 00:19:00,120 --> 00:19:02,389 though they will have a nuclear reaction equations just like this for example you 716 00:19:02,389 --> 00:19:02,399 equations just like this for example you 717 00:19:02,399 --> 00:19:05,720 equations just like this for example you have a nitrogen-14 and then you bombard 718 00:19:05,720 --> 00:19:05,730 have a nitrogen-14 and then you bombard 719 00:19:05,730 --> 00:19:09,200 have a nitrogen-14 and then you bombard it with helium and this is an alpha 720 00:19:09,200 --> 00:19:09,210 it with helium and this is an alpha 721 00:19:09,210 --> 00:19:11,720 it with helium and this is an alpha particle actually charged particle alpha 722 00:19:11,720 --> 00:19:11,730 particle actually charged particle alpha 723 00:19:11,730 --> 00:19:15,440 particle actually charged particle alpha particle and you get oxygen in fact 17 724 00:19:15,440 --> 00:19:15,450 particle and you get oxygen in fact 17 725 00:19:15,450 --> 00:19:18,980 particle and you get oxygen in fact 17 and then the hydrogen this is proton 726 00:19:18,980 --> 00:19:18,990 and then the hydrogen this is proton 727 00:19:18,990 --> 00:19:22,220 and then the hydrogen this is proton this is actually a proton and then or 728 00:19:22,220 --> 00:19:22,230 this is actually a proton and then or 729 00:19:22,230 --> 00:19:24,470 this is actually a proton and then or you can simply you write it like this or 730 00:19:24,470 --> 00:19:24,480 you can simply you write it like this or 731 00:19:24,480 --> 00:19:26,120 you can simply you write it like this or you can write it like this you see again 732 00:19:26,120 --> 00:19:26,130 you can write it like this you see again 733 00:19:26,130 --> 00:19:29,060 you can write it like this you see again the helium is alpha particle that means 734 00:19:29,060 --> 00:19:29,070 the helium is alpha particle that means 735 00:19:29,070 --> 00:19:31,159 the helium is alpha particle that means that there is a two plus charge on that 736 00:19:31,159 --> 00:19:31,169 that there is a two plus charge on that 737 00:19:31,169 --> 00:19:33,500 that there is a two plus charge on that that means it is the nucleus of the 738 00:19:33,500 --> 00:19:33,510 that means it is the nucleus of the 739 00:19:33,510 --> 00:19:36,409 that means it is the nucleus of the helium not the helium atom not the 740 00:19:36,409 --> 00:19:36,419 helium not the helium atom not the 741 00:19:36,419 --> 00:19:40,070 helium not the helium atom not the helium atom and again this 742 00:19:40,070 --> 00:19:40,080 helium atom and again this 743 00:19:40,080 --> 00:19:43,169 helium atom and again this year-11 it is not the hydrogen atom that 744 00:19:43,169 --> 00:19:43,179 year-11 it is not the hydrogen atom that 745 00:19:43,179 --> 00:19:44,999 year-11 it is not the hydrogen atom that means one proton and one electron it is 746 00:19:44,999 --> 00:19:45,009 means one proton and one electron it is 747 00:19:45,009 --> 00:19:47,549 means one proton and one electron it is only the proton and you can write that 748 00:19:47,549 --> 00:19:47,559 only the proton and you can write that 749 00:19:47,559 --> 00:19:51,090 only the proton and you can write that reaction equation like this instead of 750 00:19:51,090 --> 00:19:51,100 reaction equation like this instead of 751 00:19:51,100 --> 00:19:55,560 reaction equation like this instead of this again so nitrogen-14 bombarded with 752 00:19:55,560 --> 00:19:55,570 this again so nitrogen-14 bombarded with 753 00:19:55,570 --> 00:19:58,469 this again so nitrogen-14 bombarded with alpha particles and we end up with 754 00:19:58,469 --> 00:19:58,479 alpha particles and we end up with 755 00:19:58,479 --> 00:20:02,310 alpha particles and we end up with oxygen 17 and a proton now short way of 756 00:20:02,310 --> 00:20:02,320 oxygen 17 and a proton now short way of 757 00:20:02,320 --> 00:20:05,609 oxygen 17 and a proton now short way of writing this is this way like this you 758 00:20:05,609 --> 00:20:05,619 writing this is this way like this you 759 00:20:05,619 --> 00:20:11,070 writing this is this way like this you see again here this is called the target 760 00:20:11,070 --> 00:20:11,080 see again here this is called the target 761 00:20:11,080 --> 00:20:13,680 see again here this is called the target nucleus the nucleus of the nitrogen like 762 00:20:13,680 --> 00:20:13,690 nucleus the nucleus of the nitrogen like 763 00:20:13,690 --> 00:20:15,690 nucleus the nucleus of the nitrogen like this and this is called the product 764 00:20:15,690 --> 00:20:15,700 this and this is called the product 765 00:20:15,700 --> 00:20:18,839 this and this is called the product nucleus again that comes out and the 766 00:20:18,839 --> 00:20:18,849 nucleus again that comes out and the 767 00:20:18,849 --> 00:20:20,940 nucleus again that comes out and the first one here is the bombarding 768 00:20:20,940 --> 00:20:20,950 first one here is the bombarding 769 00:20:20,950 --> 00:20:22,859 first one here is the bombarding particles and the second one is the 770 00:20:22,859 --> 00:20:22,869 particles and the second one is the 771 00:20:22,869 --> 00:20:26,159 particles and the second one is the ejected particles you see again there is 772 00:20:26,159 --> 00:20:26,169 ejected particles you see again there is 773 00:20:26,169 --> 00:20:29,999 ejected particles you see again there is simply logic to this instead of writing 774 00:20:29,999 --> 00:20:30,009 simply logic to this instead of writing 775 00:20:30,009 --> 00:20:32,789 simply logic to this instead of writing it like this actually and this 776 00:20:32,789 --> 00:20:32,799 it like this actually and this 777 00:20:32,799 --> 00:20:35,639 it like this actually and this corresponds to a nuclear reaction 778 00:20:35,639 --> 00:20:35,649 corresponds to a nuclear reaction 779 00:20:35,649 --> 00:20:38,269 corresponds to a nuclear reaction equation and describes the 780 00:20:38,269 --> 00:20:38,279 equation and describes the 781 00:20:38,279 --> 00:20:41,609 equation and describes the transmutations actually of nitrogen to 782 00:20:41,609 --> 00:20:41,619 transmutations actually of nitrogen to 783 00:20:41,619 --> 00:20:44,759 transmutations actually of nitrogen to the oxygen 17 by bombarding with alpha 784 00:20:44,759 --> 00:20:44,769 the oxygen 17 by bombarding with alpha 785 00:20:44,769 --> 00:20:49,019 the oxygen 17 by bombarding with alpha particles now I should probably say here 786 00:20:49,019 --> 00:20:49,029 particles now I should probably say here 787 00:20:49,029 --> 00:20:54,180 particles now I should probably say here again in all these nuclear reaction 788 00:20:54,180 --> 00:20:54,190 again in all these nuclear reaction 789 00:20:54,190 --> 00:20:56,999 again in all these nuclear reaction equations they have to be balanced right 790 00:20:56,999 --> 00:20:57,009 equations they have to be balanced right 791 00:20:57,009 --> 00:20:58,619 equations they have to be balanced right we should make sure that we check that 792 00:20:58,619 --> 00:20:58,629 we should make sure that we check that 793 00:20:58,629 --> 00:21:01,889 we should make sure that we check that balance means that some of the mass 794 00:21:01,889 --> 00:21:01,899 balance means that some of the mass 795 00:21:01,899 --> 00:21:06,960 balance means that some of the mass numbers here 14 18 and here is 17 118 796 00:21:06,960 --> 00:21:06,970 numbers here 14 18 and here is 17 118 797 00:21:06,970 --> 00:21:10,710 numbers here 14 18 and here is 17 118 balances and atomic number here is 72 9 798 00:21:10,710 --> 00:21:10,720 balances and atomic number here is 72 9 799 00:21:10,720 --> 00:21:14,460 balances and atomic number here is 72 9 and here is 8 + 1 9 again so we should 800 00:21:14,460 --> 00:21:14,470 and here is 8 + 1 9 again so we should 801 00:21:14,470 --> 00:21:17,310 and here is 8 + 1 9 again so we should always have that checked and balanced 802 00:21:17,310 --> 00:21:17,320 always have that checked and balanced 803 00:21:17,320 --> 00:21:24,320 always have that checked and balanced for the nuclear equations actually now 804 00:21:24,320 --> 00:21:24,330 for the nuclear equations actually now 805 00:21:24,330 --> 00:21:26,810 for the nuclear equations actually now let's look at the kinetics of 806 00:21:26,810 --> 00:21:26,820 let's look at the kinetics of 807 00:21:26,820 --> 00:21:28,619 let's look at the kinetics of radioactive decay 808 00:21:28,619 --> 00:21:28,629 radioactive decay 809 00:21:28,629 --> 00:21:32,909 radioactive decay now all radioactive decays now decays 810 00:21:32,909 --> 00:21:32,919 now all radioactive decays now decays 811 00:21:32,919 --> 00:21:35,999 now all radioactive decays now decays not the transportation reactions 812 00:21:35,999 --> 00:21:36,009 not the transportation reactions 813 00:21:36,009 --> 00:21:39,330 not the transportation reactions actually but only the decays are first 814 00:21:39,330 --> 00:21:39,340 actually but only the decays are first 815 00:21:39,340 --> 00:21:42,299 actually but only the decays are first order processes first order processes 816 00:21:42,299 --> 00:21:42,309 order processes first order processes 817 00:21:42,309 --> 00:21:47,279 order processes first order processes and simply the kinetics of those 818 00:21:47,279 --> 00:21:47,289 and simply the kinetics of those 819 00:21:47,289 --> 00:21:52,589 and simply the kinetics of those actually will be met will be explained 820 00:21:52,589 --> 00:21:52,599 actually will be met will be explained 821 00:21:52,599 --> 00:21:53,830 actually will be met will be explained by the 822 00:21:53,830 --> 00:21:53,840 by the 823 00:21:53,840 --> 00:21:56,890 by the first order rate equations this is 824 00:21:56,890 --> 00:21:56,900 first order rate equations this is 825 00:21:56,900 --> 00:21:58,649 first order rate equations this is actually the integrated rate equation 826 00:21:58,649 --> 00:21:58,659 actually the integrated rate equation 827 00:21:58,659 --> 00:22:04,810 actually the integrated rate equation for the first order reactions now n T 828 00:22:04,810 --> 00:22:04,820 for the first order reactions now n T 829 00:22:04,820 --> 00:22:09,659 for the first order reactions now n T and sub T is the number of radioactive 830 00:22:09,659 --> 00:22:09,669 and sub T is the number of radioactive 831 00:22:09,669 --> 00:22:13,870 and sub T is the number of radioactive isotopes at time T and this corresponds 832 00:22:13,870 --> 00:22:13,880 isotopes at time T and this corresponds 833 00:22:13,880 --> 00:22:16,299 isotopes at time T and this corresponds exactly to the concentrations of the 834 00:22:16,299 --> 00:22:16,309 exactly to the concentrations of the 835 00:22:16,309 --> 00:22:18,909 exactly to the concentrations of the reactant at time T for the first order 836 00:22:18,909 --> 00:22:18,919 reactant at time T for the first order 837 00:22:18,919 --> 00:22:22,120 reactant at time T for the first order reaction right and this one here 838 00:22:22,120 --> 00:22:22,130 reaction right and this one here 839 00:22:22,130 --> 00:22:26,289 reaction right and this one here corresponds the number of ready 840 00:22:26,289 --> 00:22:26,299 corresponds the number of ready 841 00:22:26,299 --> 00:22:30,159 corresponds the number of ready radioactive isotopes at the beginning of 842 00:22:30,159 --> 00:22:30,169 radioactive isotopes at the beginning of 843 00:22:30,169 --> 00:22:32,769 radioactive isotopes at the beginning of the nuclear reaction right decay 844 00:22:32,769 --> 00:22:32,779 the nuclear reaction right decay 845 00:22:32,779 --> 00:22:36,580 the nuclear reaction right decay reaction n sub zero that means that it 846 00:22:36,580 --> 00:22:36,590 reaction n sub zero that means that it 847 00:22:36,590 --> 00:22:39,060 reaction n sub zero that means that it corresponds to the initial molar 848 00:22:39,060 --> 00:22:39,070 corresponds to the initial molar 849 00:22:39,070 --> 00:22:42,930 corresponds to the initial molar concentrations of the reactant in 850 00:22:42,930 --> 00:22:42,940 concentrations of the reactant in 851 00:22:42,940 --> 00:22:45,159 concentrations of the reactant in chemical first order reactions and 852 00:22:45,159 --> 00:22:45,169 chemical first order reactions and 853 00:22:45,169 --> 00:22:46,990 chemical first order reactions and chemical first order reactions and this 854 00:22:46,990 --> 00:22:47,000 chemical first order reactions and this 855 00:22:47,000 --> 00:22:50,200 chemical first order reactions and this K is the rate constant again and T is a 856 00:22:50,200 --> 00:22:50,210 K is the rate constant again and T is a 857 00:22:50,210 --> 00:22:54,010 K is the rate constant again and T is a time that elapsed actually and remember 858 00:22:54,010 --> 00:22:54,020 time that elapsed actually and remember 859 00:22:54,020 --> 00:22:56,620 time that elapsed actually and remember again for the first order reaction the 860 00:22:56,620 --> 00:22:56,630 again for the first order reaction the 861 00:22:56,630 --> 00:23:00,220 again for the first order reaction the half-life is independent of the initial 862 00:23:00,220 --> 00:23:00,230 half-life is independent of the initial 863 00:23:00,230 --> 00:23:02,769 half-life is independent of the initial concentrations and it is always equals 864 00:23:02,769 --> 00:23:02,779 concentrations and it is always equals 865 00:23:02,779 --> 00:23:06,549 concentrations and it is always equals to logarithm natural logarithm of two 866 00:23:06,549 --> 00:23:06,559 to logarithm natural logarithm of two 867 00:23:06,559 --> 00:23:09,909 to logarithm natural logarithm of two divided by the rate constants right and 868 00:23:09,909 --> 00:23:09,919 divided by the rate constants right and 869 00:23:09,919 --> 00:23:12,519 divided by the rate constants right and that means that the rate constant for 870 00:23:12,519 --> 00:23:12,529 that means that the rate constant for 871 00:23:12,529 --> 00:23:14,080 that means that the rate constant for the first-order reactions are always 872 00:23:14,080 --> 00:23:14,090 the first-order reactions are always 873 00:23:14,090 --> 00:23:18,700 the first-order reactions are always same no half-life is always the same no 874 00:23:18,700 --> 00:23:18,710 same no half-life is always the same no 875 00:23:18,710 --> 00:23:20,889 same no half-life is always the same no matter what is the initial concentration 876 00:23:20,889 --> 00:23:20,899 matter what is the initial concentration 877 00:23:20,899 --> 00:23:23,500 matter what is the initial concentration in this case what is the initial amount 878 00:23:23,500 --> 00:23:23,510 in this case what is the initial amount 879 00:23:23,510 --> 00:23:26,230 in this case what is the initial amount of your radioactive substance and as we 880 00:23:26,230 --> 00:23:26,240 of your radioactive substance and as we 881 00:23:26,240 --> 00:23:30,820 of your radioactive substance and as we see here half way in fact when we reach 882 00:23:30,820 --> 00:23:30,830 see here half way in fact when we reach 883 00:23:30,830 --> 00:23:35,799 see here half way in fact when we reach two they have of the reactant in this 884 00:23:35,799 --> 00:23:35,809 two they have of the reactant in this 885 00:23:35,809 --> 00:23:37,930 two they have of the reactant in this case the radioactive isotopes at the 886 00:23:37,930 --> 00:23:37,940 case the radioactive isotopes at the 887 00:23:37,940 --> 00:23:40,510 case the radioactive isotopes at the beginning the time elapsed is simply a 888 00:23:40,510 --> 00:23:40,520 beginning the time elapsed is simply a 889 00:23:40,520 --> 00:23:42,570 beginning the time elapsed is simply a half-life this is again the half-life 890 00:23:42,570 --> 00:23:42,580 half-life this is again the half-life 891 00:23:42,580 --> 00:23:45,310 half-life this is again the half-life for the first order reaction this is the 892 00:23:45,310 --> 00:23:45,320 for the first order reaction this is the 893 00:23:45,320 --> 00:23:47,260 for the first order reaction this is the logarithm natural logarithm of two 894 00:23:47,260 --> 00:23:47,270 logarithm natural logarithm of two 895 00:23:47,270 --> 00:23:50,139 logarithm natural logarithm of two divided by the rate constant T 1/2 how 896 00:23:50,139 --> 00:23:50,149 divided by the rate constant T 1/2 how 897 00:23:50,149 --> 00:23:52,210 divided by the rate constant T 1/2 how half-life is the time required for the 898 00:23:52,210 --> 00:23:52,220 half-life is the time required for the 899 00:23:52,220 --> 00:23:56,110 half-life is the time required for the half of the radio nuclei sample to decay 900 00:23:56,110 --> 00:23:56,120 half of the radio nuclei sample to decay 901 00:23:56,120 --> 00:23:58,870 half of the radio nuclei sample to decay just like chemical reactions nothing but 902 00:23:58,870 --> 00:23:58,880 just like chemical reactions nothing but 903 00:23:58,880 --> 00:24:02,460 just like chemical reactions nothing but just the chemical reactions again now 904 00:24:02,460 --> 00:24:02,470 just the chemical reactions again now 905 00:24:02,470 --> 00:24:06,490 just the chemical reactions again now the half-life of these radioactive 906 00:24:06,490 --> 00:24:06,500 the half-life of these radioactive 907 00:24:06,500 --> 00:24:07,650 the half-life of these radioactive nuclei 908 00:24:07,650 --> 00:24:07,660 nuclei 909 00:24:07,660 --> 00:24:10,740 nuclei new clients are given here again if you 910 00:24:10,740 --> 00:24:10,750 new clients are given here again if you 911 00:24:10,750 --> 00:24:14,340 new clients are given here again if you look at those let's see if I can see 912 00:24:14,340 --> 00:24:14,350 look at those let's see if I can see 913 00:24:14,350 --> 00:24:18,120 look at those let's see if I can see that here you see for example uranium 914 00:24:18,120 --> 00:24:18,130 that here you see for example uranium 915 00:24:18,130 --> 00:24:24,090 that here you see for example uranium 238 has a half-life of 4.5 times 10 to 916 00:24:24,090 --> 00:24:24,100 238 has a half-life of 4.5 times 10 to 917 00:24:24,100 --> 00:24:29,010 238 has a half-life of 4.5 times 10 to the 9 years now what does that means 918 00:24:29,010 --> 00:24:29,020 the 9 years now what does that means 919 00:24:29,020 --> 00:24:33,390 the 9 years now what does that means that simply means if you start with one 920 00:24:33,390 --> 00:24:33,400 that simply means if you start with one 921 00:24:33,400 --> 00:24:40,190 that simply means if you start with one gram of red radioactive uranium 238 and 922 00:24:40,190 --> 00:24:40,200 gram of red radioactive uranium 238 and 923 00:24:40,200 --> 00:24:44,220 gram of red radioactive uranium 238 and after billion years that 10 to the 9 924 00:24:44,220 --> 00:24:44,230 after billion years that 10 to the 9 925 00:24:44,230 --> 00:24:46,050 after billion years that 10 to the 9 right somewhere 926 00:24:46,050 --> 00:24:46,060 right somewhere 927 00:24:46,060 --> 00:24:49,770 right somewhere 4.5 billion years you will still have 928 00:24:49,770 --> 00:24:49,780 4.5 billion years you will still have 929 00:24:49,780 --> 00:24:53,190 4.5 billion years you will still have the half of that that means 0.5 gram of 930 00:24:53,190 --> 00:24:53,200 the half of that that means 0.5 gram of 931 00:24:53,200 --> 00:24:56,930 the half of that that means 0.5 gram of uranium 238 still emitted and 932 00:24:56,930 --> 00:24:56,940 uranium 238 still emitted and 933 00:24:56,940 --> 00:25:00,870 uranium 238 still emitted and radioactive right still emitting there 934 00:25:00,870 --> 00:25:00,880 radioactive right still emitting there 935 00:25:00,880 --> 00:25:03,960 radioactive right still emitting there so the half-life is really important 936 00:25:03,960 --> 00:25:03,970 so the half-life is really important 937 00:25:03,970 --> 00:25:07,020 so the half-life is really important particularly for the radioactive nucleus 938 00:25:07,020 --> 00:25:07,030 particularly for the radioactive nucleus 939 00:25:07,030 --> 00:25:10,220 particularly for the radioactive nucleus because it tells you how far you will 940 00:25:10,220 --> 00:25:10,230 because it tells you how far you will 941 00:25:10,230 --> 00:25:12,510 because it tells you how far you will simply introduce to the radiation 942 00:25:12,510 --> 00:25:12,520 simply introduce to the radiation 943 00:25:12,520 --> 00:25:16,950 simply introduce to the radiation nuclear radiations from those now again 944 00:25:16,950 --> 00:25:16,960 nuclear radiations from those now again 945 00:25:16,960 --> 00:25:21,750 nuclear radiations from those now again if you look at the other species here 946 00:25:21,750 --> 00:25:21,760 if you look at the other species here 947 00:25:21,760 --> 00:25:25,230 if you look at the other species here for example 235 half-life is less than 948 00:25:25,230 --> 00:25:25,240 for example 235 half-life is less than 949 00:25:25,240 --> 00:25:27,570 for example 235 half-life is less than that but it is 10 to the 8 years that's 950 00:25:27,570 --> 00:25:27,580 that but it is 10 to the 8 years that's 951 00:25:27,580 --> 00:25:32,000 that but it is 10 to the 8 years that's a long time and then we have for example 952 00:25:32,000 --> 00:25:32,010 a long time and then we have for example 953 00:25:32,010 --> 00:25:37,380 a long time and then we have for example strontium 90 half-life is 28.8 years and 954 00:25:37,380 --> 00:25:37,390 strontium 90 half-life is 28.8 years and 955 00:25:37,390 --> 00:25:41,270 strontium 90 half-life is 28.8 years and if you have iodine 131 half-life is 956 00:25:41,270 --> 00:25:41,280 if you have iodine 131 half-life is 957 00:25:41,280 --> 00:25:46,230 if you have iodine 131 half-life is about 0.02 that means about 2 months 958 00:25:46,230 --> 00:25:46,240 about 0.02 that means about 2 months 959 00:25:46,240 --> 00:25:47,100 about 0.02 that means about 2 months right 960 00:25:47,100 --> 00:25:47,110 right 961 00:25:47,110 --> 00:25:50,880 right about 2 months so and these are the type 962 00:25:50,880 --> 00:25:50,890 about 2 months so and these are the type 963 00:25:50,890 --> 00:25:55,260 about 2 months so and these are the type of decay that they emit then again alpha 964 00:25:55,260 --> 00:25:55,270 of decay that they emit then again alpha 965 00:25:55,270 --> 00:25:58,560 of decay that they emit then again alpha alpha alpha beta beta alpha beta and 966 00:25:58,560 --> 00:25:58,570 alpha alpha beta beta alpha beta and 967 00:25:58,570 --> 00:26:10,430 alpha alpha beta beta alpha beta and beta again now by using this first-order 968 00:26:10,430 --> 00:26:10,440 beta again now by using this first-order 969 00:26:10,440 --> 00:26:16,680 beta again now by using this first-order rate law we can in fact determine the 970 00:26:16,680 --> 00:26:16,690 rate law we can in fact determine the 971 00:26:16,690 --> 00:26:20,790 rate law we can in fact determine the age of the rocks which contains 972 00:26:20,790 --> 00:26:20,800 age of the rocks which contains 973 00:26:20,800 --> 00:26:25,680 age of the rocks which contains reactive isotopes such as uranium right 974 00:26:25,680 --> 00:26:25,690 reactive isotopes such as uranium right 975 00:26:25,690 --> 00:26:30,630 reactive isotopes such as uranium right or we can determine any objects that 976 00:26:30,630 --> 00:26:30,640 or we can determine any objects that 977 00:26:30,640 --> 00:26:34,380 or we can determine any objects that contains a radioactive isotopes if we 978 00:26:34,380 --> 00:26:34,390 contains a radioactive isotopes if we 979 00:26:34,390 --> 00:26:37,620 contains a radioactive isotopes if we know what is the radioactive isotope is 980 00:26:37,620 --> 00:26:37,630 know what is the radioactive isotope is 981 00:26:37,630 --> 00:26:40,800 know what is the radioactive isotope is now particularly if you have wooden 982 00:26:40,800 --> 00:26:40,810 now particularly if you have wooden 983 00:26:40,810 --> 00:26:45,950 now particularly if you have wooden objects right and they have carbons and 984 00:26:45,950 --> 00:26:45,960 objects right and they have carbons and 985 00:26:45,960 --> 00:26:50,100 objects right and they have carbons and the carbon isotopes we have carbon 12 is 986 00:26:50,100 --> 00:26:50,110 the carbon isotopes we have carbon 12 is 987 00:26:50,110 --> 00:26:52,620 the carbon isotopes we have carbon 12 is the stable isotope most stabilizers 988 00:26:52,620 --> 00:26:52,630 the stable isotope most stabilizers 989 00:26:52,630 --> 00:26:54,660 the stable isotope most stabilizers herbs not radioactive and we have carbon 990 00:26:54,660 --> 00:26:54,670 herbs not radioactive and we have carbon 991 00:26:54,670 --> 00:26:58,920 herbs not radioactive and we have carbon 13 and we also have carbon 14 carbon 14 992 00:26:58,920 --> 00:26:58,930 13 and we also have carbon 14 carbon 14 993 00:26:58,930 --> 00:27:02,070 13 and we also have carbon 14 carbon 14 is a radioactive isotopes it is not 994 00:27:02,070 --> 00:27:02,080 is a radioactive isotopes it is not 995 00:27:02,080 --> 00:27:06,180 is a radioactive isotopes it is not stable and it decays actually and we 996 00:27:06,180 --> 00:27:06,190 stable and it decays actually and we 997 00:27:06,190 --> 00:27:10,830 stable and it decays actually and we have five of the carbon 14 half isotope 998 00:27:10,830 --> 00:27:10,840 have five of the carbon 14 half isotope 999 00:27:10,840 --> 00:27:16,200 have five of the carbon 14 half isotope radioactive isotope is 5,700 years now 1000 00:27:16,200 --> 00:27:16,210 radioactive isotope is 5,700 years now 1001 00:27:16,210 --> 00:27:19,110 radioactive isotope is 5,700 years now it is limited to the objects up to about 1002 00:27:19,110 --> 00:27:19,120 it is limited to the objects up to about 1003 00:27:19,120 --> 00:27:22,970 it is limited to the objects up to about in fact by using this carbon-14 1004 00:27:22,970 --> 00:27:22,980 in fact by using this carbon-14 1005 00:27:22,980 --> 00:27:27,660 in fact by using this carbon-14 determining the activity of carbon-14 in 1006 00:27:27,660 --> 00:27:27,670 determining the activity of carbon-14 in 1007 00:27:27,670 --> 00:27:29,670 determining the activity of carbon-14 in the wooden objects we can determine the 1008 00:27:29,670 --> 00:27:29,680 the wooden objects we can determine the 1009 00:27:29,680 --> 00:27:32,970 the wooden objects we can determine the age of those objects which is made of 1010 00:27:32,970 --> 00:27:32,980 age of those objects which is made of 1011 00:27:32,980 --> 00:27:37,980 age of those objects which is made of wood as a matter of fact and how far we 1012 00:27:37,980 --> 00:27:37,990 wood as a matter of fact and how far we 1013 00:27:37,990 --> 00:27:42,150 wood as a matter of fact and how far we can go back again by dating again by 1014 00:27:42,150 --> 00:27:42,160 can go back again by dating again by 1015 00:27:42,160 --> 00:27:44,880 can go back again by dating again by using this carbon-14 dating we can go up 1016 00:27:44,880 --> 00:27:44,890 using this carbon-14 dating we can go up 1017 00:27:44,890 --> 00:27:53,100 using this carbon-14 dating we can go up to 50000 year again now we can also use 1018 00:27:53,100 --> 00:27:53,110 to 50000 year again now we can also use 1019 00:27:53,110 --> 00:27:56,970 to 50000 year again now we can also use other isotopes to date the rocks the age 1020 00:27:56,970 --> 00:27:56,980 other isotopes to date the rocks the age 1021 00:27:56,980 --> 00:27:59,670 other isotopes to date the rocks the age of the rocks actually now as we will see 1022 00:27:59,670 --> 00:27:59,680 of the rocks actually now as we will see 1023 00:27:59,680 --> 00:28:05,880 of the rocks actually now as we will see why this is the limit because when we 1024 00:28:05,880 --> 00:28:05,890 why this is the limit because when we 1025 00:28:05,890 --> 00:28:08,340 why this is the limit because when we use as we will see when I solve the 1026 00:28:08,340 --> 00:28:08,350 use as we will see when I solve the 1027 00:28:08,350 --> 00:28:13,800 use as we will see when I solve the problem related to this what we assume 1028 00:28:13,800 --> 00:28:13,810 problem related to this what we assume 1029 00:28:13,810 --> 00:28:22,860 problem related to this what we assume that carbon-14 abundance in let's say 1030 00:28:22,860 --> 00:28:22,870 that carbon-14 abundance in let's say 1031 00:28:22,870 --> 00:28:26,850 that carbon-14 abundance in let's say ten thousand years or twenty thousand 1032 00:28:26,850 --> 00:28:26,860 ten thousand years or twenty thousand 1033 00:28:26,860 --> 00:28:30,300 ten thousand years or twenty thousand years or forty thousand years before in 1034 00:28:30,300 --> 00:28:30,310 years or forty thousand years before in 1035 00:28:30,310 --> 00:28:33,600 years or forty thousand years before in the air is exactly the same as the 1036 00:28:33,600 --> 00:28:33,610 the air is exactly the same as the 1037 00:28:33,610 --> 00:28:35,040 the air is exactly the same as the carbon food 1038 00:28:35,040 --> 00:28:35,050 carbon food 1039 00:28:35,050 --> 00:28:39,180 carbon food abundance in the air today and when we 1040 00:28:39,180 --> 00:28:39,190 abundance in the air today and when we 1041 00:28:39,190 --> 00:28:41,070 abundance in the air today and when we say in when I say in the air what we 1042 00:28:41,070 --> 00:28:41,080 say in when I say in the air what we 1043 00:28:41,080 --> 00:28:43,620 say in when I say in the air what we have that carries the carbon in the air 1044 00:28:43,620 --> 00:28:43,630 have that carries the carbon in the air 1045 00:28:43,630 --> 00:28:45,930 have that carries the carbon in the air is carbon dioxide carbon dioxide right 1046 00:28:45,930 --> 00:28:45,940 is carbon dioxide carbon dioxide right 1047 00:28:45,940 --> 00:28:55,170 is carbon dioxide carbon dioxide right so simply the ratio of carbon 14 to the 1048 00:28:55,170 --> 00:28:55,180 so simply the ratio of carbon 14 to the 1049 00:28:55,180 --> 00:28:59,040 so simply the ratio of carbon 14 to the other carbons let's say in 40 years ago 1050 00:28:59,040 --> 00:28:59,050 other carbons let's say in 40 years ago 1051 00:28:59,050 --> 00:29:06,840 other carbons let's say in 40 years ago in the atmosphere in a carbon dioxide if 1052 00:29:06,840 --> 00:29:06,850 in the atmosphere in a carbon dioxide if 1053 00:29:06,850 --> 00:29:11,040 in the atmosphere in a carbon dioxide if is if it is the same that means that the 1054 00:29:11,040 --> 00:29:11,050 is if it is the same that means that the 1055 00:29:11,050 --> 00:29:14,250 is if it is the same that means that the living organisms which inhale uses 1056 00:29:14,250 --> 00:29:14,260 living organisms which inhale uses 1057 00:29:14,260 --> 00:29:17,490 living organisms which inhale uses carbon dioxide from the air will also 1058 00:29:17,490 --> 00:29:17,500 carbon dioxide from the air will also 1059 00:29:17,500 --> 00:29:22,410 carbon dioxide from the air will also have the carbon 14 abundances I should 1060 00:29:22,410 --> 00:29:22,420 have the carbon 14 abundances I should 1061 00:29:22,420 --> 00:29:27,120 have the carbon 14 abundances I should say in their bodies or in the plants the 1062 00:29:27,120 --> 00:29:27,130 say in their bodies or in the plants the 1063 00:29:27,130 --> 00:29:31,380 say in their bodies or in the plants the same as the air same as the air and by 1064 00:29:31,380 --> 00:29:31,390 same as the air same as the air and by 1065 00:29:31,390 --> 00:29:34,860 same as the air same as the air and by assuming that actually we calculate the 1066 00:29:34,860 --> 00:29:34,870 assuming that actually we calculate the 1067 00:29:34,870 --> 00:29:37,530 assuming that actually we calculate the age of the artifacts which is made from 1068 00:29:37,530 --> 00:29:37,540 age of the artifacts which is made from 1069 00:29:37,540 --> 00:29:39,870 age of the artifacts which is made from the wood or other living organisms 1070 00:29:39,870 --> 00:29:39,880 the wood or other living organisms 1071 00:29:39,880 --> 00:29:44,220 the wood or other living organisms actually now and before 50 thousand 1072 00:29:44,220 --> 00:29:44,230 actually now and before 50 thousand 1073 00:29:44,230 --> 00:29:46,770 actually now and before 50 thousand years before let's say 55 thousand years 1074 00:29:46,770 --> 00:29:46,780 years before let's say 55 thousand years 1075 00:29:46,780 --> 00:29:51,230 years before let's say 55 thousand years ago we can't be sure maybe that the 1076 00:29:51,230 --> 00:29:51,240 ago we can't be sure maybe that the 1077 00:29:51,240 --> 00:29:55,170 ago we can't be sure maybe that the carbon-14 ratio to the other carbons in 1078 00:29:55,170 --> 00:29:55,180 carbon-14 ratio to the other carbons in 1079 00:29:55,180 --> 00:29:57,960 carbon-14 ratio to the other carbons in the carbon dioxide that many years ago 1080 00:29:57,960 --> 00:29:57,970 the carbon dioxide that many years ago 1081 00:29:57,970 --> 00:30:00,420 the carbon dioxide that many years ago was probably not the same as that we 1082 00:30:00,420 --> 00:30:00,430 was probably not the same as that we 1083 00:30:00,430 --> 00:30:02,700 was probably not the same as that we have today in the atmosphere we have 1084 00:30:02,700 --> 00:30:02,710 have today in the atmosphere we have 1085 00:30:02,710 --> 00:30:07,590 have today in the atmosphere we have today in the atmosphere let's just take 1086 00:30:07,590 --> 00:30:07,600 today in the atmosphere let's just take 1087 00:30:07,600 --> 00:30:09,270 today in the atmosphere let's just take an example let's see if I have an 1088 00:30:09,270 --> 00:30:09,280 an example let's see if I have an 1089 00:30:09,280 --> 00:30:18,510 an example let's see if I have an example here I guess now 1090 00:30:18,510 --> 00:30:18,520 1091 00:30:18,520 --> 00:30:23,360 before that I will solve problems 1092 00:30:23,360 --> 00:30:23,370 before that I will solve problems 1093 00:30:23,370 --> 00:30:36,240 before that I will solve problems related to this carbon dating let me 1094 00:30:36,240 --> 00:30:36,250 related to this carbon dating let me 1095 00:30:36,250 --> 00:31:09,910 related to this carbon dating let me find out the problem that I picked up 1096 00:31:09,910 --> 00:31:09,920 1097 00:31:09,920 --> 00:31:14,350 now let's let's see I have that no I 1098 00:31:14,350 --> 00:31:14,360 now let's let's see I have that no I 1099 00:31:14,360 --> 00:31:24,700 now let's let's see I have that no I don't have it 1100 00:31:24,700 --> 00:31:24,710 1101 00:31:24,710 --> 00:31:31,600 this is the from the book I picked it up 1102 00:31:31,600 --> 00:31:31,610 this is the from the book I picked it up 1103 00:31:31,610 --> 00:31:44,060 this is the from the book I picked it up simple exercise 21-6 is not installed it 1104 00:31:44,060 --> 00:31:44,070 simple exercise 21-6 is not installed it 1105 00:31:44,070 --> 00:31:51,260 simple exercise 21-6 is not installed it says it's simple exercise exercise - no 1106 00:31:51,260 --> 00:31:51,270 says it's simple exercise exercise - no 1107 00:31:51,270 --> 00:31:59,779 says it's simple exercise exercise - no this is that twenty one six one two just 1108 00:31:59,779 --> 00:31:59,789 this is that twenty one six one two just 1109 00:31:59,789 --> 00:32:07,600 this is that twenty one six one two just two and it will be twenty one six and 1110 00:32:07,600 --> 00:32:07,610 1111 00:32:07,610 --> 00:32:12,560 this is the second one there it says a 1112 00:32:12,560 --> 00:32:12,570 this is the second one there it says a 1113 00:32:12,570 --> 00:32:20,600 this is the second one there it says a wooden object has an activity of carbon 1114 00:32:20,600 --> 00:32:20,610 wooden object has an activity of carbon 1115 00:32:20,610 --> 00:32:25,610 wooden object has an activity of carbon 14 measured to be as 11.6 disintegration 1116 00:32:25,610 --> 00:32:25,620 14 measured to be as 11.6 disintegration 1117 00:32:25,620 --> 00:32:37,960 14 measured to be as 11.6 disintegration per second so it wouldn't object 1118 00:32:37,960 --> 00:32:37,970 1119 00:32:37,970 --> 00:32:44,110 this is an old object certainly old 1120 00:32:44,110 --> 00:32:44,120 1121 00:32:44,120 --> 00:32:47,770 measured to be activity of carbon 14 1122 00:32:47,770 --> 00:32:47,780 measured to be activity of carbon 14 1123 00:32:47,780 --> 00:32:59,740 measured to be activity of carbon 14 measured let's say activity of carbon 14 1124 00:32:59,740 --> 00:32:59,750 measured let's say activity of carbon 14 1125 00:32:59,750 --> 00:33:04,149 measured let's say activity of carbon 14 equals to eleven point six 1126 00:33:04,149 --> 00:33:04,159 equals to eleven point six 1127 00:33:04,159 --> 00:33:19,720 equals to eleven point six disintegration per second 1128 00:33:19,720 --> 00:33:19,730 1129 00:33:19,730 --> 00:33:36,450 now fresh wood activity carbon-14 is 1130 00:33:36,450 --> 00:33:36,460 now fresh wood activity carbon-14 is 1131 00:33:36,460 --> 00:33:45,549 now fresh wood activity carbon-14 is 15.2 disintegration per second now this 1132 00:33:45,549 --> 00:33:45,559 15.2 disintegration per second now this 1133 00:33:45,559 --> 00:33:50,289 15.2 disintegration per second now this is again the first order reaction right 1134 00:33:50,289 --> 00:33:50,299 is again the first order reaction right 1135 00:33:50,299 --> 00:33:53,649 is again the first order reaction right first order reaction and we will use the 1136 00:33:53,649 --> 00:33:53,659 first order reaction and we will use the 1137 00:33:53,659 --> 00:33:59,370 first order reaction and we will use the first order rate law Ln n T over N 0 1138 00:33:59,370 --> 00:33:59,380 first order rate law Ln n T over N 0 1139 00:33:59,380 --> 00:34:05,909 first order rate law Ln n T over N 0 equals 2 minus K times T and the 1140 00:34:05,909 --> 00:34:05,919 equals 2 minus K times T and the 1141 00:34:05,919 --> 00:34:10,030 equals 2 minus K times T and the half-life of carbon 1142 00:34:10,030 --> 00:34:10,040 half-life of carbon 1143 00:34:10,040 --> 00:34:14,159 half-life of carbon I guess another data here T 1/2 for 1144 00:34:14,159 --> 00:34:14,169 I guess another data here T 1/2 for 1145 00:34:14,169 --> 00:34:23,470 I guess another data here T 1/2 for carbon-14 is given as 5,700 years this 1146 00:34:23,470 --> 00:34:23,480 carbon-14 is given as 5,700 years this 1147 00:34:23,480 --> 00:34:27,659 carbon-14 is given as 5,700 years this is the half-life 1148 00:34:27,659 --> 00:34:27,669 1149 00:34:27,669 --> 00:34:31,270 ok now let's think about that let me 1150 00:34:31,270 --> 00:34:31,280 ok now let's think about that let me 1151 00:34:31,280 --> 00:34:33,550 ok now let's think about that let me explain what this disintegration per 1152 00:34:33,550 --> 00:34:33,560 explain what this disintegration per 1153 00:34:33,560 --> 00:34:37,180 explain what this disintegration per second means that simply means that in 1154 00:34:37,180 --> 00:34:37,190 second means that simply means that in 1155 00:34:37,190 --> 00:34:40,540 second means that simply means that in one second that can be measured by using 1156 00:34:40,540 --> 00:34:40,550 one second that can be measured by using 1157 00:34:40,550 --> 00:34:43,300 one second that can be measured by using instruments geiger instruments measuring 1158 00:34:43,300 --> 00:34:43,310 instruments geiger instruments measuring 1159 00:34:43,310 --> 00:34:47,230 instruments geiger instruments measuring the disintegration radiations right this 1160 00:34:47,230 --> 00:34:47,240 the disintegration radiations right this 1161 00:34:47,240 --> 00:34:51,059 the disintegration radiations right this simply means that in one second 1162 00:34:51,059 --> 00:34:51,069 simply means that in one second 1163 00:34:51,069 --> 00:34:58,240 simply means that in one second average 11.6 carbon-14 decays right in 1164 00:34:58,240 --> 00:34:58,250 average 11.6 carbon-14 decays right in 1165 00:34:58,250 --> 00:35:04,170 average 11.6 carbon-14 decays right in one second to the product nucleus 1166 00:35:04,170 --> 00:35:04,180 one second to the product nucleus 1167 00:35:04,180 --> 00:35:11,530 one second to the product nucleus whatever and this one is the fresh wood 1168 00:35:11,530 --> 00:35:11,540 whatever and this one is the fresh wood 1169 00:35:11,540 --> 00:35:14,579 whatever and this one is the fresh wood that means if you take a piece of wood 1170 00:35:14,579 --> 00:35:14,589 that means if you take a piece of wood 1171 00:35:14,589 --> 00:35:18,359 that means if you take a piece of wood outside and measure the carbon-14 1172 00:35:18,359 --> 00:35:18,369 outside and measure the carbon-14 1173 00:35:18,369 --> 00:35:23,010 outside and measure the carbon-14 activity in that case we have 15.2 1174 00:35:23,010 --> 00:35:23,020 activity in that case we have 15.2 1175 00:35:23,020 --> 00:35:26,200 activity in that case we have 15.2 disintegration per second now remember 1176 00:35:26,200 --> 00:35:26,210 disintegration per second now remember 1177 00:35:26,210 --> 00:35:31,300 disintegration per second now remember the disintegration per second let's put 1178 00:35:31,300 --> 00:35:31,310 the disintegration per second let's put 1179 00:35:31,310 --> 00:35:33,420 the disintegration per second let's put it this way and 1180 00:35:33,420 --> 00:35:33,430 it this way and 1181 00:35:33,430 --> 00:35:44,089 it this way and she simply the number of carbon-14 1182 00:35:44,089 --> 00:35:44,099 1183 00:35:44,099 --> 00:35:50,640 nuclides now this will simply be 1184 00:35:50,640 --> 00:35:50,650 nuclides now this will simply be 1185 00:35:50,650 --> 00:35:58,730 nuclides now this will simply be proportional to the number of carbon-14 1186 00:35:58,730 --> 00:35:58,740 proportional to the number of carbon-14 1187 00:35:58,740 --> 00:36:09,410 proportional to the number of carbon-14 disintegration per second right because 1188 00:36:09,410 --> 00:36:09,420 disintegration per second right because 1189 00:36:09,420 --> 00:36:12,240 disintegration per second right because just like concentration you can think 1190 00:36:12,240 --> 00:36:12,250 just like concentration you can think 1191 00:36:12,250 --> 00:36:14,160 just like concentration you can think about that as concentration the more 1192 00:36:14,160 --> 00:36:14,170 about that as concentration the more 1193 00:36:14,170 --> 00:36:16,670 about that as concentration the more carbon-14 I have the more 1194 00:36:16,670 --> 00:36:16,680 carbon-14 I have the more 1195 00:36:16,680 --> 00:36:18,990 carbon-14 I have the more disintegrations will be per second it is 1196 00:36:18,990 --> 00:36:19,000 disintegrations will be per second it is 1197 00:36:19,000 --> 00:36:22,579 disintegrations will be per second it is just that rate sort of the rate and so 1198 00:36:22,579 --> 00:36:22,589 just that rate sort of the rate and so 1199 00:36:22,589 --> 00:36:28,020 just that rate sort of the rate and so when that is correct that means that n 0 1200 00:36:28,020 --> 00:36:28,030 when that is correct that means that n 0 1201 00:36:28,030 --> 00:36:30,260 when that is correct that means that n 0 if I take that and zero the initially 1202 00:36:30,260 --> 00:36:30,270 if I take that and zero the initially 1203 00:36:30,270 --> 00:36:33,809 if I take that and zero the initially when this object is made from the fresh 1204 00:36:33,809 --> 00:36:33,819 when this object is made from the fresh 1205 00:36:33,819 --> 00:36:37,400 when this object is made from the fresh would at that time so many years ago 1206 00:36:37,400 --> 00:36:37,410 would at that time so many years ago 1207 00:36:37,410 --> 00:36:43,829 would at that time so many years ago this is the number of carbon-14 let's 1208 00:36:43,829 --> 00:36:43,839 this is the number of carbon-14 let's 1209 00:36:43,839 --> 00:36:48,109 this is the number of carbon-14 let's say in that object and that will also be 1210 00:36:48,109 --> 00:36:48,119 say in that object and that will also be 1211 00:36:48,119 --> 00:36:54,240 say in that object and that will also be number of nucleotides proportional to 1212 00:36:54,240 --> 00:36:54,250 number of nucleotides proportional to 1213 00:36:54,250 --> 00:36:56,809 number of nucleotides proportional to the number of carbon-13 disintegrations 1214 00:36:56,809 --> 00:36:56,819 the number of carbon-13 disintegrations 1215 00:36:56,819 --> 00:37:01,970 the number of carbon-13 disintegrations initially let's say number of carbon-14 1216 00:37:01,970 --> 00:37:01,980 initially let's say number of carbon-14 1217 00:37:01,980 --> 00:37:04,859 initially let's say number of carbon-14 disintegration per second initially this 1218 00:37:04,859 --> 00:37:04,869 disintegration per second initially this 1219 00:37:04,869 --> 00:37:10,950 disintegration per second initially this is initially what does that means that 1220 00:37:10,950 --> 00:37:10,960 is initially what does that means that 1221 00:37:10,960 --> 00:37:14,700 is initially what does that means that means that instead of in this equation 1222 00:37:14,700 --> 00:37:14,710 means that instead of in this equation 1223 00:37:14,710 --> 00:37:19,109 means that instead of in this equation here since the that number of 1224 00:37:19,109 --> 00:37:19,119 here since the that number of 1225 00:37:19,119 --> 00:37:20,849 here since the that number of disintegration is proportional to the 1226 00:37:20,849 --> 00:37:20,859 disintegration is proportional to the 1227 00:37:20,859 --> 00:37:24,359 disintegration is proportional to the number of the carbon-14 nucleons instead 1228 00:37:24,359 --> 00:37:24,369 number of the carbon-14 nucleons instead 1229 00:37:24,369 --> 00:37:27,990 number of the carbon-14 nucleons instead of the number of carbon-14 nucleus here 1230 00:37:27,990 --> 00:37:28,000 of the number of carbon-14 nucleus here 1231 00:37:28,000 --> 00:37:30,480 of the number of carbon-14 nucleus here and here I can take the number of this 1232 00:37:30,480 --> 00:37:30,490 and here I can take the number of this 1233 00:37:30,490 --> 00:37:32,789 and here I can take the number of this integrations right because they are 1234 00:37:32,789 --> 00:37:32,799 integrations right because they are 1235 00:37:32,799 --> 00:37:34,530 integrations right because they are proportional there will be a constant 1236 00:37:34,530 --> 00:37:34,540 proportional there will be a constant 1237 00:37:34,540 --> 00:37:36,030 proportional there will be a constant probably those councils will cancel out 1238 00:37:36,030 --> 00:37:36,040 probably those councils will cancel out 1239 00:37:36,040 --> 00:37:39,720 probably those councils will cancel out so I can simply put up set up my 1240 00:37:39,720 --> 00:37:39,730 so I can simply put up set up my 1241 00:37:39,730 --> 00:37:43,500 so I can simply put up set up my equation as follow I can have Ln and up 1242 00:37:43,500 --> 00:37:43,510 equation as follow I can have Ln and up 1243 00:37:43,510 --> 00:37:47,010 equation as follow I can have Ln and up here for NT I will simply 1244 00:37:47,010 --> 00:37:47,020 here for NT I will simply 1245 00:37:47,020 --> 00:37:51,270 here for NT I will simply have this number of this integration 1246 00:37:51,270 --> 00:37:51,280 have this number of this integration 1247 00:37:51,280 --> 00:38:00,090 have this number of this integration which is 11.6 and for n 0 in this 1248 00:38:00,090 --> 00:38:00,100 which is 11.6 and for n 0 in this 1249 00:38:00,100 --> 00:38:04,940 which is 11.6 and for n 0 in this equation here I will take number of 1250 00:38:04,940 --> 00:38:04,950 1251 00:38:04,950 --> 00:38:08,580 integration per second as 15.2 from the 1252 00:38:08,580 --> 00:38:08,590 integration per second as 15.2 from the 1253 00:38:08,590 --> 00:38:15,960 integration per second as 15.2 from the fresh you see again as the decay or 1254 00:38:15,960 --> 00:38:15,970 fresh you see again as the decay or 1255 00:38:15,970 --> 00:38:19,160 fresh you see again as the decay or nuclear reaction continues the number of 1256 00:38:19,160 --> 00:38:19,170 nuclear reaction continues the number of 1257 00:38:19,170 --> 00:38:23,810 nuclear reaction continues the number of carbon-14 decreases and reaches to 1258 00:38:23,810 --> 00:38:23,820 carbon-14 decreases and reaches to 1259 00:38:23,820 --> 00:38:26,490 carbon-14 decreases and reaches to simply from here to there and that time 1260 00:38:26,490 --> 00:38:26,500 simply from here to there and that time 1261 00:38:26,500 --> 00:38:36,510 simply from here to there and that time now the question here is why does it 1262 00:38:36,510 --> 00:38:36,520 now the question here is why does it 1263 00:38:36,520 --> 00:38:43,140 now the question here is why does it decreases right carbon-14 now as long as 1264 00:38:43,140 --> 00:38:43,150 decreases right carbon-14 now as long as 1265 00:38:43,150 --> 00:38:50,010 decreases right carbon-14 now as long as the plant is alive it will simply take 1266 00:38:50,010 --> 00:38:50,020 the plant is alive it will simply take 1267 00:38:50,020 --> 00:38:52,880 the plant is alive it will simply take carbon dioxide from the atmosphere 1268 00:38:52,880 --> 00:38:52,890 carbon dioxide from the atmosphere 1269 00:38:52,890 --> 00:38:56,880 carbon dioxide from the atmosphere during the day and then converted to the 1270 00:38:56,880 --> 00:38:56,890 during the day and then converted to the 1271 00:38:56,890 --> 00:38:59,280 during the day and then converted to the sugars and then at night 1272 00:38:59,280 --> 00:38:59,290 sugars and then at night 1273 00:38:59,290 --> 00:39:01,530 sugars and then at night it will give the carbon dioxide to the 1274 00:39:01,530 --> 00:39:01,540 it will give the carbon dioxide to the 1275 00:39:01,540 --> 00:39:04,140 it will give the carbon dioxide to the atmosphere and there's always an 1276 00:39:04,140 --> 00:39:04,150 atmosphere and there's always an 1277 00:39:04,150 --> 00:39:07,310 atmosphere and there's always an equilibrium between the carbon-14 1278 00:39:07,310 --> 00:39:07,320 equilibrium between the carbon-14 1279 00:39:07,320 --> 00:39:11,280 equilibrium between the carbon-14 concentration in the living organisms 1280 00:39:11,280 --> 00:39:11,290 concentration in the living organisms 1281 00:39:11,290 --> 00:39:14,960 concentration in the living organisms let's say plant and the outside 1282 00:39:14,960 --> 00:39:14,970 let's say plant and the outside 1283 00:39:14,970 --> 00:39:18,840 let's say plant and the outside atmospheric concentrations of carbon-14 1284 00:39:18,840 --> 00:39:18,850 atmospheric concentrations of carbon-14 1285 00:39:18,850 --> 00:39:21,420 atmospheric concentrations of carbon-14 in the carbon dioxide atmosphere carbon 1286 00:39:21,420 --> 00:39:21,430 in the carbon dioxide atmosphere carbon 1287 00:39:21,430 --> 00:39:27,090 in the carbon dioxide atmosphere carbon dioxide but when the plant dies you cut 1288 00:39:27,090 --> 00:39:27,100 dioxide but when the plant dies you cut 1289 00:39:27,100 --> 00:39:31,260 dioxide but when the plant dies you cut the wood for example right and from that 1290 00:39:31,260 --> 00:39:31,270 the wood for example right and from that 1291 00:39:31,270 --> 00:39:34,740 the wood for example right and from that point on there will be no photosynthesis 1292 00:39:34,740 --> 00:39:34,750 point on there will be no photosynthesis 1293 00:39:34,750 --> 00:39:37,580 point on there will be no photosynthesis that means there will be no exchange of 1294 00:39:37,580 --> 00:39:37,590 that means there will be no exchange of 1295 00:39:37,590 --> 00:39:41,130 that means there will be no exchange of carbon dioxide from the atmosphere with 1296 00:39:41,130 --> 00:39:41,140 carbon dioxide from the atmosphere with 1297 00:39:41,140 --> 00:39:45,540 carbon dioxide from the atmosphere with the wood whatever in the wood when it's 1298 00:39:45,540 --> 00:39:45,550 the wood whatever in the wood when it's 1299 00:39:45,550 --> 00:39:49,970 the wood whatever in the wood when it's cut off will decrease carbon-14 amount 1300 00:39:49,970 --> 00:39:49,980 cut off will decrease carbon-14 amount 1301 00:39:49,980 --> 00:39:52,050 cut off will decrease carbon-14 amount concentration will decrease as the time 1302 00:39:52,050 --> 00:39:52,060 concentration will decrease as the time 1303 00:39:52,060 --> 00:39:54,240 concentration will decrease as the time goes on and then from that decrease 1304 00:39:54,240 --> 00:39:54,250 goes on and then from that decrease 1305 00:39:54,250 --> 00:39:57,840 goes on and then from that decrease actually we calculate the age of the 1306 00:39:57,840 --> 00:39:57,850 actually we calculate the age of the 1307 00:39:57,850 --> 00:39:59,840 actually we calculate the age of the wood that 1308 00:39:59,840 --> 00:39:59,850 wood that 1309 00:39:59,850 --> 00:40:02,810 wood that it's cut off when they cut off okay so 1310 00:40:02,810 --> 00:40:02,820 it's cut off when they cut off okay so 1311 00:40:02,820 --> 00:40:05,570 it's cut off when they cut off okay so you see again this is eleven point six 1312 00:40:05,570 --> 00:40:05,580 you see again this is eleven point six 1313 00:40:05,580 --> 00:40:08,450 you see again this is eleven point six and this is five point seven this will 1314 00:40:08,450 --> 00:40:08,460 and this is five point seven this will 1315 00:40:08,460 --> 00:40:14,780 and this is five point seven this will be equals to minus simply K but instead 1316 00:40:14,780 --> 00:40:14,790 be equals to minus simply K but instead 1317 00:40:14,790 --> 00:40:17,270 be equals to minus simply K but instead of minus K what we can put for the 1318 00:40:17,270 --> 00:40:17,280 of minus K what we can put for the 1319 00:40:17,280 --> 00:40:18,470 of minus K what we can put for the first-order reactions 1320 00:40:18,470 --> 00:40:18,480 first-order reactions 1321 00:40:18,480 --> 00:40:23,870 first-order reactions Ln two divided by half life right Ln 2 1322 00:40:23,870 --> 00:40:23,880 Ln two divided by half life right Ln 2 1323 00:40:23,880 --> 00:40:26,090 Ln two divided by half life right Ln 2 divided by half life so I can put here 1324 00:40:26,090 --> 00:40:26,100 divided by half life so I can put here 1325 00:40:26,100 --> 00:40:31,900 divided by half life so I can put here Ln two divided by half life which is 1326 00:40:31,900 --> 00:40:31,910 Ln two divided by half life which is 1327 00:40:31,910 --> 00:40:37,870 Ln two divided by half life which is 5,700 years right and time T this is it 1328 00:40:37,870 --> 00:40:37,880 5,700 years right and time T this is it 1329 00:40:37,880 --> 00:40:42,950 5,700 years right and time T this is it so now I have all the numbers everything 1330 00:40:42,950 --> 00:40:42,960 so now I have all the numbers everything 1331 00:40:42,960 --> 00:40:46,540 so now I have all the numbers everything here and the only thing I have to simply 1332 00:40:46,540 --> 00:40:46,550 here and the only thing I have to simply 1333 00:40:46,550 --> 00:40:51,170 here and the only thing I have to simply find out the T and if I solve for T here 1334 00:40:51,170 --> 00:40:51,180 find out the T and if I solve for T here 1335 00:40:51,180 --> 00:40:53,480 find out the T and if I solve for T here and it turns out to be let's see how 1336 00:40:53,480 --> 00:40:53,490 and it turns out to be let's see how 1337 00:40:53,490 --> 00:40:58,300 and it turns out to be let's see how much what result I found out I find out 1338 00:40:58,300 --> 00:40:58,310 much what result I found out I find out 1339 00:40:58,310 --> 00:41:02,090 much what result I found out I find out two thousand two hundred and twenty 1340 00:41:02,090 --> 00:41:02,100 two thousand two hundred and twenty 1341 00:41:02,100 --> 00:41:08,980 two thousand two hundred and twenty years so this is actually called 1342 00:41:08,980 --> 00:41:08,990 years so this is actually called 1343 00:41:08,990 --> 00:41:12,220 years so this is actually called carbon-14 Gator 1344 00:41:12,220 --> 00:41:12,230 carbon-14 Gator 1345 00:41:12,230 --> 00:41:17,090 carbon-14 Gator you date the objects but again in order 1346 00:41:17,090 --> 00:41:17,100 you date the objects but again in order 1347 00:41:17,100 --> 00:41:20,690 you date the objects but again in order to carry out this method you have to 1348 00:41:20,690 --> 00:41:20,700 to carry out this method you have to 1349 00:41:20,700 --> 00:41:24,890 to carry out this method you have to have carbon in your object right again 1350 00:41:24,890 --> 00:41:24,900 have carbon in your object right again 1351 00:41:24,900 --> 00:41:27,890 have carbon in your object right again you just assume that carbon 1352 00:41:27,890 --> 00:41:27,900 you just assume that carbon 1353 00:41:27,900 --> 00:41:30,430 you just assume that carbon concentration in that object when that 1354 00:41:30,430 --> 00:41:30,440 concentration in that object when that 1355 00:41:30,440 --> 00:41:35,050 concentration in that object when that cut off or die was the same as the 1356 00:41:35,050 --> 00:41:35,060 cut off or die was the same as the 1357 00:41:35,060 --> 00:41:37,370 cut off or die was the same as the carbon-14 concentrations in the 1358 00:41:37,370 --> 00:41:37,380 carbon-14 concentrations in the 1359 00:41:37,380 --> 00:41:41,480 carbon-14 concentrations in the atmosphere at that time right when it's 1360 00:41:41,480 --> 00:41:41,490 atmosphere at that time right when it's 1361 00:41:41,490 --> 00:41:44,750 atmosphere at that time right when it's cut off it stopped the exchange of the 1362 00:41:44,750 --> 00:41:44,760 cut off it stopped the exchange of the 1363 00:41:44,760 --> 00:41:47,090 cut off it stopped the exchange of the carbon dioxide with the atmosphere that 1364 00:41:47,090 --> 00:41:47,100 carbon dioxide with the atmosphere that 1365 00:41:47,100 --> 00:41:50,090 carbon dioxide with the atmosphere that means the present carbon-14 will decay 1366 00:41:50,090 --> 00:41:50,100 means the present carbon-14 will decay 1367 00:41:50,100 --> 00:41:53,030 means the present carbon-14 will decay decrease and decrease according to the 1368 00:41:53,030 --> 00:41:53,040 decrease and decrease according to the 1369 00:41:53,040 --> 00:41:55,010 decrease and decrease according to the first-order reaction and we find out 1370 00:41:55,010 --> 00:41:55,020 first-order reaction and we find out 1371 00:41:55,020 --> 00:41:58,310 first-order reaction and we find out what time is elapsed to decrease the 1372 00:41:58,310 --> 00:41:58,320 what time is elapsed to decrease the 1373 00:41:58,320 --> 00:42:01,670 what time is elapsed to decrease the carbon-14 to the value which is 1374 00:42:01,670 --> 00:42:01,680 carbon-14 to the value which is 1375 00:42:01,680 --> 00:42:04,310 carbon-14 to the value which is proportional to this actually as a 1376 00:42:04,310 --> 00:42:04,320 proportional to this actually as a 1377 00:42:04,320 --> 00:42:07,340 proportional to this actually as a matter of fact and we calculate this now 1378 00:42:07,340 --> 00:42:07,350 matter of fact and we calculate this now 1379 00:42:07,350 --> 00:42:10,130 matter of fact and we calculate this now the question here is is there an error 1380 00:42:10,130 --> 00:42:10,140 the question here is is there an error 1381 00:42:10,140 --> 00:42:13,850 the question here is is there an error there sure I mean I can say maybe 1382 00:42:13,850 --> 00:42:13,860 there sure I mean I can say maybe 1383 00:42:13,860 --> 00:42:17,480 there sure I mean I can say maybe like pause - fifty years but still it is 1384 00:42:17,480 --> 00:42:17,490 like pause - fifty years but still it is 1385 00:42:17,490 --> 00:42:19,160 like pause - fifty years but still it is pretty good I mean it's really working 1386 00:42:19,160 --> 00:42:19,170 pretty good I mean it's really working 1387 00:42:19,170 --> 00:42:20,780 pretty good I mean it's really working pretty good as a matter of fact it he 1388 00:42:20,780 --> 00:42:20,790 pretty good as a matter of fact it he 1389 00:42:20,790 --> 00:42:22,820 pretty good as a matter of fact it he goes up to 20 thousand years twenty five 1390 00:42:22,820 --> 00:42:22,830 goes up to 20 thousand years twenty five 1391 00:42:22,830 --> 00:42:25,370 goes up to 20 thousand years twenty five thousand years sometimes you know and so 1392 00:42:25,370 --> 00:42:25,380 thousand years sometimes you know and so 1393 00:42:25,380 --> 00:42:26,990 thousand years sometimes you know and so hundred years there 1394 00:42:26,990 --> 00:42:27,000 hundred years there 1395 00:42:27,000 --> 00:42:28,520 hundred years there compared to twenty five thousand years 1396 00:42:28,520 --> 00:42:28,530 compared to twenty five thousand years 1397 00:42:28,530 --> 00:42:31,220 compared to twenty five thousand years is not that long even that so it really 1398 00:42:31,220 --> 00:42:31,230 is not that long even that so it really 1399 00:42:31,230 --> 00:42:35,510 is not that long even that so it really works fine there is another example I 1400 00:42:35,510 --> 00:42:35,520 works fine there is another example I 1401 00:42:35,520 --> 00:42:38,870 works fine there is another example I was going to show not only the carbon-14 1402 00:42:38,870 --> 00:42:38,880 was going to show not only the carbon-14 1403 00:42:38,880 --> 00:42:42,830 was going to show not only the carbon-14 that can be used for datin old artifacts 1404 00:42:42,830 --> 00:42:42,840 that can be used for datin old artifacts 1405 00:42:42,840 --> 00:42:45,350 that can be used for datin old artifacts and objects you can also use other 1406 00:42:45,350 --> 00:42:45,360 and objects you can also use other 1407 00:42:45,360 --> 00:42:50,360 and objects you can also use other radioactive isotopes such as uranium 238 1408 00:42:50,360 --> 00:42:50,370 radioactive isotopes such as uranium 238 1409 00:42:50,370 --> 00:42:53,300 radioactive isotopes such as uranium 238 and by using the uranium 238 you can 1410 00:42:53,300 --> 00:42:53,310 and by using the uranium 238 you can 1411 00:42:53,310 --> 00:42:56,470 and by using the uranium 238 you can determine the age of the rocks 1412 00:42:56,470 --> 00:42:56,480 determine the age of the rocks 1413 00:42:56,480 --> 00:43:00,530 determine the age of the rocks remember the half-life of uranium is ten 1414 00:43:00,530 --> 00:43:00,540 remember the half-life of uranium is ten 1415 00:43:00,540 --> 00:43:04,780 remember the half-life of uranium is ten to the nine years something right and 1416 00:43:04,780 --> 00:43:04,790 to the nine years something right and 1417 00:43:04,790 --> 00:43:10,820 to the nine years something right and actually the age of the earth which is 1418 00:43:10,820 --> 00:43:10,830 actually the age of the earth which is 1419 00:43:10,830 --> 00:43:16,040 actually the age of the earth which is assumed to be 4.5 billion years came odd 1420 00:43:16,040 --> 00:43:16,050 assumed to be 4.5 billion years came odd 1421 00:43:16,050 --> 00:43:21,110 assumed to be 4.5 billion years came odd from this age or dating of the rocks 1422 00:43:21,110 --> 00:43:21,120 from this age or dating of the rocks 1423 00:43:21,120 --> 00:43:22,850 from this age or dating of the rocks which contains uranium 1424 00:43:22,850 --> 00:43:22,860 which contains uranium 1425 00:43:22,860 --> 00:43:28,280 which contains uranium it contains uranium again assuming that 1426 00:43:28,280 --> 00:43:28,290 it contains uranium again assuming that 1427 00:43:28,290 --> 00:43:33,920 it contains uranium again assuming that the uranium we know the activity of the 1428 00:43:33,920 --> 00:43:33,930 the uranium we know the activity of the 1429 00:43:33,930 --> 00:43:38,480 the uranium we know the activity of the uranium now there again there is a 1430 00:43:38,480 --> 00:43:38,490 uranium now there again there is a 1431 00:43:38,490 --> 00:43:40,430 uranium now there again there is a problem here I also picked up probably 1432 00:43:40,430 --> 00:43:40,440 problem here I also picked up probably 1433 00:43:40,440 --> 00:43:42,710 problem here I also picked up probably next time I will work out on it you use 1434 00:43:42,710 --> 00:43:42,720 next time I will work out on it you use 1435 00:43:42,720 --> 00:43:45,380 next time I will work out on it you use a different approach actually by using 1436 00:43:45,380 --> 00:43:45,390 a different approach actually by using 1437 00:43:45,390 --> 00:43:49,430 a different approach actually by using the uranium 238 for Dayton because the 1438 00:43:49,430 --> 00:43:49,440 the uranium 238 for Dayton because the 1439 00:43:49,440 --> 00:43:51,560 the uranium 238 for Dayton because the end product there is led you look at the 1440 00:43:51,560 --> 00:43:51,570 end product there is led you look at the 1441 00:43:51,570 --> 00:43:53,450 end product there is led you look at the amount of lead you compare it with the 1442 00:43:53,450 --> 00:43:53,460 amount of lead you compare it with the 1443 00:43:53,460 --> 00:43:56,840 amount of lead you compare it with the amount of uranium 238 present in the 1444 00:43:56,840 --> 00:43:56,850 amount of uranium 238 present in the 1445 00:43:56,850 --> 00:43:58,970 amount of uranium 238 present in the rock and from there again using the 1446 00:43:58,970 --> 00:43:58,980 rock and from there again using the 1447 00:43:58,980 --> 00:44:01,280 rock and from there again using the first-order rate though integrated rate 1448 00:44:01,280 --> 00:44:01,290 first-order rate though integrated rate 1449 00:44:01,290 --> 00:44:03,500 first-order rate though integrated rate law you calculate the age of the rocks 1450 00:44:03,500 --> 00:44:03,510 law you calculate the age of the rocks 1451 00:44:03,510 --> 00:44:06,460 law you calculate the age of the rocks and they turn out to be like three 1452 00:44:06,460 --> 00:44:06,470 and they turn out to be like three 1453 00:44:06,470 --> 00:44:10,310 and they turn out to be like three million something like you know years 1454 00:44:10,310 --> 00:44:10,320 million something like you know years 1455 00:44:10,320 --> 00:44:13,700 million something like you know years and they assume that cooling of the 1456 00:44:13,700 --> 00:44:13,710 and they assume that cooling of the 1457 00:44:13,710 --> 00:44:17,320 and they assume that cooling of the earth took about a million billion years 1458 00:44:17,320 --> 00:44:17,330 earth took about a million billion years 1459 00:44:17,330 --> 00:44:20,740 earth took about a million billion years so if you measure age of a rock like 1460 00:44:20,740 --> 00:44:20,750 so if you measure age of a rock like 1461 00:44:20,750 --> 00:44:23,090 so if you measure age of a rock like three and a three and a half billion 1462 00:44:23,090 --> 00:44:23,100 three and a three and a half billion 1463 00:44:23,100 --> 00:44:24,059 three and a three and a half billion years then 1464 00:44:24,059 --> 00:44:24,069 years then 1465 00:44:24,069 --> 00:44:25,739 years then age of the earth must be about 1466 00:44:25,739 --> 00:44:25,749 age of the earth must be about 1467 00:44:25,749 --> 00:44:27,509 age of the earth must be about four-and-a-half billion years 1468 00:44:27,509 --> 00:44:27,519 four-and-a-half billion years 1469 00:44:27,519 --> 00:44:30,779 four-and-a-half billion years right because that's what I assumed 1 1470 00:44:30,779 --> 00:44:30,789 right because that's what I assumed 1 1471 00:44:30,789 --> 00:44:34,249 right because that's what I assumed 1 billion year to cool off the earth and 1472 00:44:34,249 --> 00:44:34,259 billion year to cool off the earth and 1473 00:44:34,259 --> 00:44:38,459 billion year to cool off the earth and formations of those rocks and from that 1474 00:44:38,459 --> 00:44:38,469 formations of those rocks and from that 1475 00:44:38,469 --> 00:44:40,289 formations of those rocks and from that on you can determine the age of the rock 1476 00:44:40,289 --> 00:44:40,299 on you can determine the age of the rock 1477 00:44:40,299 --> 00:44:50,910 on you can determine the age of the rock actually ok any questions yes now this 1478 00:44:50,910 --> 00:44:50,920 actually ok any questions yes now this 1479 00:44:50,920 --> 00:44:53,939 actually ok any questions yes now this one here now remember for the first 1480 00:44:53,939 --> 00:44:53,949 one here now remember for the first 1481 00:44:53,949 --> 00:44:57,799 one here now remember for the first order reaction the rate constant is 1482 00:44:57,799 --> 00:44:57,809 order reaction the rate constant is 1483 00:44:57,809 --> 00:45:01,380 order reaction the rate constant is equals to Ln 2 divided by T or T 1484 00:45:01,380 --> 00:45:01,390 equals to Ln 2 divided by T or T 1485 00:45:01,390 --> 00:45:03,749 equals to Ln 2 divided by T or T half-life remember that for the first 1486 00:45:03,749 --> 00:45:03,759 half-life remember that for the first 1487 00:45:03,759 --> 00:45:06,120 half-life remember that for the first order reaction let's write it down T 1 1488 00:45:06,120 --> 00:45:06,130 order reaction let's write it down T 1 1489 00:45:06,130 --> 00:45:10,789 order reaction let's write it down T 1 half-life is equal to Ln 2 divided by K 1490 00:45:10,789 --> 00:45:10,799 half-life is equal to Ln 2 divided by K 1491 00:45:10,799 --> 00:45:18,059 half-life is equal to Ln 2 divided by K or K is equal to Ln 2 divided by T 1/2 1492 00:45:18,059 --> 00:45:18,069 or K is equal to Ln 2 divided by T 1/2 1493 00:45:18,069 --> 00:45:23,309 or K is equal to Ln 2 divided by T 1/2 laugh ok so instead of rate constant you 1494 00:45:23,309 --> 00:45:23,319 laugh ok so instead of rate constant you 1495 00:45:23,319 --> 00:45:27,269 laugh ok so instead of rate constant you put Ln 2 divided by half life but that's 1496 00:45:27,269 --> 00:45:27,279 put Ln 2 divided by half life but that's 1497 00:45:27,279 --> 00:45:30,630 put Ln 2 divided by half life but that's only for the first order reaction we can 1498 00:45:30,630 --> 00:45:30,640 only for the first order reaction we can 1499 00:45:30,640 --> 00:45:32,789 only for the first order reaction we can do this for the chemical reaction first 1500 00:45:32,789 --> 00:45:32,799 do this for the chemical reaction first 1501 00:45:32,799 --> 00:45:35,249 do this for the chemical reaction first order chemical reactions all nuclear 1502 00:45:35,249 --> 00:45:35,259 order chemical reactions all nuclear 1503 00:45:35,259 --> 00:45:38,459 order chemical reactions all nuclear decay reactions are first order first 1504 00:45:38,459 --> 00:45:38,469 decay reactions are first order first 1505 00:45:38,469 --> 00:45:43,589 decay reactions are first order first order reactions okay I guess we stop 1506 00:45:43,589 --> 00:45:43,599 order reactions okay I guess we stop 1507 00:45:43,599 --> 00:45:45,869 order reactions okay I guess we stop here