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A compound contains 87.4% Nitrogen and 12.6% Hydrogen. If the molar mass of the compound is 32.05 g/mol, what is the molecular formula?

User Ascotan
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Final answer:

The molecular formula of the compound is (NH2)2, which means it contains 2 nitrogen atoms and 4 hydrogen atoms. Dividing the molar mass of the compound (32.05 g/mol) by the molar mass of the empirical formula (16.03 g/mol), we find a ratio of 2. Therefore, the molecular formula of the compound is (NH2)2.

Step-by-step explanation:

To find the molecular formula of the compound, we need to determine its empirical formula. From the given information, we can calculate the number of moles of each element in the compound: Assuming a 100g sample, there would be 87.4g of Nitrogen and 12.6g of Hydrogen. Next, we need to find the simplest whole-number ratio of moles between N and H. Dividing the moles of each element by the smaller number of moles (6.24 mol in this case), we get N = 6.24 mol / 6.24 mol = 1 and H = 12.47 mol / 6.24 mol = 2.

Therefore, the empirical formula of the compound is NH2. To find the molecular formula, we need to know the molar mass of the compound. The molar mass of the empirical formula (NH2) is 14.01 g/mol (N) + 2(1.01 g/mol) (H) = 16.03 g/mol. Dividing the molar mass of the compound (32.05 g/mol) by the molar mass of the empirical formula (16.03 g/mol), we find a ratio of 2. Therefore, the molecular formula of the compound is (NH2)2.

User David Merinos
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