Question

What will be the ratio of partial pressures of $10$ moles of $He$ and $5$ moles of $C{H}_4$ present in a reaction mixture?

• A. $1:2$
• B. $2:1$
• C. $1:3$
• D. $3:1$

Answer 1

The correct option is B $2:1$

Let $P^{\circ }$ be the total pressure.
$\therefore p_{He}=P^{\circ }\times \frac{10}{15}$ (1)
$p_{C{H}_3}=P^{\circ }\times \frac{5}{15}$ (2)
$\frac{p_{He}}{p_{C{H}_3}}=\frac{10}{5}$
Thus the ratio is $2:1$.