Question

Minimum mass of hydrocarbon which, on combustion produces $44g$ of $C{O}_2$ and $18g$ of $H_{2}O$, is:

• A. 16 g
• B. 14 g
• C. 32 g
• D. 28 g

Answer 1

Answer: (B)

14 g

44 g of carbon dioxide corresponds to 1 mole and 18 g of water corresponds to 1 mole of water. Thus, our hydrocarbon contains 1 mole of C atoms for every 2 moles of hydrogen atoms. The empirical formula of the hydrocarbon is $C{H}_2$.

Minimum mass of a real hydrocarbon of this empirical formula will be that of $C{H}_2$. Hence, minimum mass of hydrocarbon which, on combustion produces 44g of $C{O}_2$ and 18g of $H_{2}O$, is 14 g.