0:00:00.000,0:00:03.670 I want to make a quick correction 0:00:03.680,0:00:05.860 to my second oxidation video. 0:00:05.860,0:00:07.800 It was pointed out that I made an error 0:00:07.810,0:00:09.610 that you will probably find confusing. 0:00:09.620,0:00:12.250 So I had written down hydrogen peroxide. 0:00:12.250,0:00:16.030 Because this was one of the situations or the special cases 0:00:16.050,0:00:19.590 where oxygen's oxidation state 0:00:19.600,0:00:21.200 isn't necessarily minus 2. 0:00:21.210,0:00:25.200 So hydrogen peroxide is 2 hydrogens, 2 oxygens. 0:00:25.230,0:00:27.960 And it's structure looks like this. 0:00:27.970,0:00:30.000 The oxygens are bonded to each other, 0:00:30.000,0:00:33.080 and they're each bonded to a hydrogen. 0:00:33.090,0:00:36.420 And we know oxygen is really electronegative. 0:00:36.430,0:00:37.950 It likes to hog electrons. 0:00:37.960,0:00:39.020 And I said that in that video. 0:00:39.040,0:00:40.260 And because it hogs electrons, 0:00:40.270,0:00:44.200 the hydrogens lose their electron to oxygen, 0:00:44.200,0:00:46.340 or at least from the oxidation state point of view. 0:00:46.340,0:00:50.330 So they each have a plus 1 oxidation state, 0:00:50.340,0:00:51.910 which I did say in that video. 0:00:51.910,0:00:54.170 And then I went on and my brain was clearly 0:00:54.180,0:00:57.360 -- and this is actually a good point for you to realize 0:00:57.370,0:00:58.830 how confusing this can sometimes be 0:00:58.840,0:01:00.340 if you're not careful with your work. 0:01:00.350,0:01:02.100 I say in the last video, 0:01:02.110,0:01:04.750 and obviously oxygen gains an electron. 0:01:04.770,0:01:07.770 And then I say and it's oxidation state is plus 1. 0:01:07.780,0:01:10.240 Which clearly makes no sense. 0:01:10.250,0:01:12.160 If you gain an electron, 0:01:12.180,0:01:15.000 that will reduce your oxidation state. 0:01:15.000,0:01:16.800 It will reduce that hypothetical charge. 0:01:16.810,0:01:19.980 And so your oxidation state is minus 1 0:01:19.990,0:01:21.910 in each of these oxygens. 0:01:21.930,0:01:24.180 And, of course, this is a special case 0:01:24.190,0:01:26.880 because traditionally, oxygen in the case 0:01:26.890,0:01:29.030 I always show it with, is in water. 0:01:29.040,0:01:31.620 When it takes 2 electrons, 0:01:31.640,0:01:33.880 1 from this hydrogen and 1 from that hydrogen, 0:01:33.890,0:01:36.120 it normally has an oxidation state of minus 2 0:01:36.140,0:01:37.600 and, of course, in this case, 0:01:37.610,0:01:39.640 it's plus 1 and plus 1 for the 2 hydrogens. 0:01:39.640,0:01:43.770 I think later, when I go back to the molecular formula, 0:01:43.790,0:01:45.230 I kind of corrected in my head. 0:01:45.240,0:01:46.640 But I want to be very clear to you. 0:01:46.640,0:01:50.210 Oxygen does not have an oxidation state of plus 1 0:01:50.230,0:01:51.280 in hydrogen peroxide. 0:01:51.290,0:01:52.380 It is minus 1. 0:01:52.390,0:01:54.090 I said it gained the electrons, 0:01:54.100,0:01:56.550 but then my brain obviously heard the word gaining 0:01:56.570,0:01:58.190 and wanted to put a plus sign there. 0:01:58.200,0:02:01.580 No. It gained an electron that reduces the oxygen. 0:02:01.600,0:02:06.340 It makes its oxidation state minus 1 for hydrogen peroxide. 0:02:06.360,0:02:07.890 So hydrogen peroxide has 0:02:07.910,0:02:12.440 2 hydrogens with a plus 1 oxidation state. 0:02:12.450,0:02:16.000 And it has 2 oxygens with a minus 1 oxidation state. 0:02:16.020,0:02:19.700 One times 2 minus 1 times 2 is equal to 0, 0:02:19.710,0:02:21.910 so we're all cool.