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A gaseous hydrocarbon gives upon combustion 0.72 g of water and 3.08 g of CO2. The empirical formula of the hydrocarbon is -

1. C6H5
2. C7H8
3. C2H4
4. C3H4

Correct answer: C7H8

Solution

The correct option, C7H8, is determined by calculating the moles of carbon and hydrogen from the combustion products. The mass of CO2 indicates the amount of carbon, while the mass of water indicates the amount of hydrogen, leading to a ratio that corresponds to the empirical formula C7H8.

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