Question

The partial pressure of hydrogen in a flask containing $2g$ of hydrogen and $32g$ of sulphur dioxide is:

• A. $1/{16}^{th}$ of the total pressure
• B. $1/9^{th}$ of the total pressure
• C. $2/3^{rd}$ of the total pressure
• D. $1/8^{th}$ of the total pressure

Answer 1

The correct option is C $2/3^{rd}$ of the total pressure

$n_{H_2}=\frac{2\text{g}}{2\text{g/mol}}=1\text{mol}$
and$n_{S{O}_2}=\frac{32\text{g}}{64\text{g/mol}}=0.5\text{mol}$
So, partial pressure willl be:
$\therefore P_{H_2}=\frac{n_{H_2}}{(n_{H_2}+n_{S{O}_2})}\times P_T=\frac{1}{(1+0.5)}\times P_T=\frac{2}{3}{P}_T$
Therefore, the partial pressure of hydrogen is ${2/3}^{rd}$ of total pressure.