Question

Equal weights of methane and hydrogen are mixed in an empty container ${25}^{\circ }C$. The fraction of the total pressure exerted by hydrogen is

• A. $\frac{1}{2}$
• B. $\frac{8}{9}$
• C. $\frac{1}{9}$
• D. $\frac{16}{17}$

Answer 1

Answer: (B)

$\frac{8}{9}$

Let $x$ g of both be mixed.

$Molesof{H}_2=\frac{x}{2}$

$MolesofC{H}_4=\frac{x}{16}$

$Molefractionof{H}_2=\frac{x/2}{\left(x/2\right)+\left(x/16\right)}=\frac{8}{9}$

which is also the fraction of total pressure executed by $H_2$.

Therefore, the correct option is $B$