Q14 / 155 · WBJEE 2020 · Chemistry
Equal masses of ethane and hydrogen are mixed in a empty container at $298 \mathrm{~K}$. The fraction of total pressure exerted by hydrogen is
- Correct answerA$15: 16$
- B$1: 1$
- C$1: 4$
- D$1: 6$
Solution
Hint:
Let mass of ethane and $\mathrm{H}_{2}$ are $\mathrm{xg}$.
$\begin{array}{c}
n_{\mathrm{H}_{2}}=\frac{\mathrm{x}}{2} \text { and } \mathrm{n}_{\mathrm{C}_{2} \mathrm{H}_{\mathrm{z}}}=\frac{\mathrm{x}}{30} \\
\frac{\mathrm{P}_{\mathrm{H}_{2}}}{\mathrm{P}_{\mathrm{T}}}=\frac{\mathrm{n}_{\mathrm{H}_{2}}}{\mathrm{n}_{\mathrm{H}_{2}}+\mathrm{n}_{\mathrm{C}_{2} \mathrm{H}}}=\frac{\frac{\mathrm{x}}{2}}{\frac{\mathrm{X}}{2}+\frac{\mathrm{x}}{30}}=\frac{15}{16}
\end{array}$
Hence, the correct answer is option: 'A'.