Midterm Q3

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Natalie_Martinez_1I
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Joined: Mon Feb 26, 2018 3:00 am

Midterm Q3

Postby Natalie_Martinez_1I » Wed Jun 13, 2018 4:50 pm

For this question how are we supposed to know that oxygen isn't in the empirical formula of nicotine?
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Jared Pagal 1J
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Re: Midterm Q3

Postby Jared Pagal 1J » Wed Jun 13, 2018 10:47 pm

This problem is a combustion problem so we know that one of the reactants is O2, and given the products of CO2, H2O, and N, we know that the oxygen in the products comes from O2. This would mean that C,H, and N make up nicotine. Also I believe during that midterm he told us it was CHN

Natalie_Martinez_1I
Posts: 30
Joined: Mon Feb 26, 2018 3:00 am

Re: Midterm Q3

Postby Natalie_Martinez_1I » Thu Jun 14, 2018 1:53 am

But in other problems there have been compounds that included oxygen in the empirical formula so how can we assume that O2 is the only thing that contributes to all the oxygen?

Chem_Mod
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Re: Midterm Q3

Postby Chem_Mod » Thu Jun 14, 2018 4:23 pm

You can add up the mass of C, H, N which you can determine to see if this adds up to the mass of the sample that was combusted. You will find that it is approximately equal to (within experimental uncertainty) to the mass of burnt sample. So, there is no mass contribution by the oxygen.


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