## M19

Daniel Lai
Posts: 65
Joined: Fri Sep 28, 2018 12:28 am

### M19

This question was really hard. I looked at the books method, and it didn't make any sense. I did it a different way by determining the coefficients of the other terms using empirical method. Did anyone else do it this way???

Chem_Mod
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Joined: Thu Aug 04, 2011 1:53 pm
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### Re: M19

The hardest part about this problem is determining how much oxygen is in the caffeine. Because the reactants include caffeine, which has oxygen, and oxygen itself, we can't just add up all the oxygens in the products and use that to figure out how much oxygen was in caffeine (some of that came from the sole oxygen reactant). Thus, you'd have to find the masses of individual elements in your products (C, N, and H), and then subtract these from the mass of caffeine given. The result will represent the mass of oxygen in caffeine, and you can then convert your numbers into moles, divide them all by the lowest mole number, and find the empirical formula ratio.