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On complete combustion 1.0 g of an organic compound (X) gave 1.46 g of CO2 and 0.567 g of H2O. The empirical formula mass of compound (X) is (Given molar mass in g mol^-1 : C : 12, H : 1, O : 16)

1. 30
2. 60
3. 15
4. 45

Correct answer: 30

Solution

To find the empirical formula mass, we first determine the moles of carbon and hydrogen produced from the combustion products. The mass of CO2 indicates the amount of carbon, and the mass of H2O indicates the amount of hydrogen. Calculating the moles gives us 0.04 moles of C and 0.0635 moles of H, leading to a ratio of 1:1.5, which simplifies to 2:3. The empirical formula is C2H3, and its mass is 30 g/mol.

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