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Caffeine, a stimulant found in coffee and soda, has the mass percent composition: c, 49.48%; h, 5.19%; n, 28.85%; o, 16.48%. the molar mass of caffeine is 194.19 g/mol. part a find the molecular formula of caffeine. express your answer as a chemical formula

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Assuming 1 mole of caffeine, therefore the mass is 194.19 grams.

C = 0.4948 * 194.19 grams * (1 mol / 12 grams) = 8

H = 0.0519 * 194.19 grams * (1 mol / 1 grams) = 10

N = 0.2885 * 194.19 grams * (1 mol / 14 grams) = 4

O = 0.1648 * 194.19 grams * (1 mol / 16 grams) = 2

 

So the molecular formula is:

C8H10N4O2