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Hi there.
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In this video i will be discussing problem number 15.
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And problem number 15 wants to know, first of all, two things.
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It wants to know how to determine isotopic abundances experimentally.
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And the way to do that is to use a mass spectrophotometer.
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And this works because a mass spectrophotometer will measure a charge to mass ratio.
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So for the element you are looking for, or that you're looking at, you will use a gaseous positive ion of that and put it in the mass spectrophotometer.
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And that will give you peaks that give you relative abundance.
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So perhaps you have a peak there, a much smaller peak there.
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All right.
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So perhaps you get something like this.
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This means that there are four different isotopes.
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And then the size of the peak tells you the relative abundance.
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So you can get that information that way.
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The reason this works is the answer to part b, how isotopes differ.
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Isotopes differ by their number of neutrons...