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jaersyn
Determine the molecular formula of a compound given the following percent composition: N, 30.4% and O, 69.6% and a molecular mass of 92.
Since the molar mass of N and O are about the same (14 and 16), and the percentage of O is roughly twice that of N, the ratio of N to O is 1:2. Since NO2 has a mass of 46 and 92/46 equals 2, you double the formula to get your answer: N2O4