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Chemistry · Some Basic Concepts of Chemistry
हिन्दीUnder identical conditions of temperature and pressure, \( 60\text{ mL} \) of a gaseous hydrocarbon requires \( 300\text{ mL} \) of dioxygen for complete combustion and produces \( 180\text{ mL} \) of carbon dioxide. The molecular formula of the hydrocarbon is:
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Correct answer · Option B
\( \text{C}_3\text{H}_8 \)
Explanation
For \( \text{C}_x\text{H}_y + (x + y/4)\text{O}_2 \rightarrow x\text{CO}_2 + (y/2)\text{H}_2\text{O} \), by Gay Lussac's law: \( x = 180/60 = 3 \) and \( x + y/4 = 300/60 = 5 \implies y/4 = 2 \implies y = 8 \). Thus, the hydrocarbon is \( \text{C}_3\text{H}_8 \).
