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0.5 g of an organic compound on combustion gave 1.46 g of CO2 and 0.9 g of H2O. The percentage of carbon in the compound is _____. (Nearest integer) [Given : Molar mass (in g mol−1) : C : 12, H : 1, O : 16]

1. 80
2. 79
3. 78
4. 81

Correct answer: 80

Solution

To find the percentage of carbon in the compound, we first calculate the moles of CO2 produced, which indicates the amount of carbon. Since 1 mole of CO2 contains 1 mole of carbon, we find the moles of carbon from the mass of CO2, then convert that to grams of carbon and calculate the percentage based on the original mass of the compound. This results in approximately 80% carbon content.

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