WEBVTT

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I want to make a quick correction

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to my second oxidation video.

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It was pointed out that I made an error

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that you will probably find confusing.

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So I had written down hydrogen peroxide.

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Because this was one of the situations or the special cases

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where oxygen's oxidation state

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isn't necessarily minus 2.

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So hydrogen peroxide is 2 hydrogens, 2 oxygens.

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And it's structure looks like this.

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The oxygens are bonded to each other,

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and they're each bonded to a hydrogen.

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And we know oxygen is really electronegative.

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It likes to hog electrons.

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And I said that in that video.

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And because it hogs electrons,

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the hydrogens lose their electron to oxygen,

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or at least from the oxidation state point of view.

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So they each have a plus 1 oxidation state,

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which I did say in that video.

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And then I went on and my brain was clearly

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-- and this is actually a good point for you to realize

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how confusing this can sometimes be

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if you're not careful with your work.

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I say in the last video,

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and obviously oxygen gains an electron.

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And then I say and it's oxidation state is plus 1.

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Which clearly makes no sense.

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If you gain an electron,

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that will reduce your oxidation state.

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It will reduce that hypothetical charge.

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And so your oxidation state is minus 1

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in each of these oxygens.

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And, of course, this is a special case

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because traditionally, oxygen in the case

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I always show it with, is in water.

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When it takes 2 electrons,

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1 from this hydrogen and 1 from that hydrogen,

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it normally has an oxidation state of minus 2

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and, of course, in this case,

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it's plus 1 and plus 1 for the 2 hydrogens.

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I think later, when I go back to the molecular formula,

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I kind of corrected in my head.

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But I want to be very clear to you.

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Oxygen does not have an oxidation state of plus 1

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in hydrogen peroxide.

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It is minus 1.

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I said it gained the electrons,

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but then my brain obviously heard the word gaining

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and wanted to put a plus sign there.

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No. It gained an electron that reduces the oxygen.

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It makes its oxidation state minus 1 for hydrogen peroxide.

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So hydrogen peroxide has

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2 hydrogens with a plus 1 oxidation state.

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And it has 2 oxygens with a minus 1 oxidation state.

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One times 2 minus 1 times 2 is equal to 0,

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so we're all cool.