Question

' $x$ ' $g$ of molecular oxygen $\left(O_2\right)$ is mixed with $200g$ of neon $(Ne)$. The total pressure of the non-reactive mixture of $O_2$ and $Ne$ in the cylinder is 25 bar. The partial pressure of $Ne$ is $20$ bar at the same temperature and volume. The value of ' $x$ ' is ______
[Given: Molar mass of $O_2=32gmo{l}^{-1}$. Molar mass of $Ne=20gmo{l}^{-1}]$

Answer 1

Answer: 80

$O_2+Ne$
Xgm 200 gm
$P_{\text{total }}=25\text{ bar };P_{Ne}=20$
$P_{O_2}+P_{Ne}=25$
$P_{O_2}=25-20=5\text{ bar }$
$5=\frac{\frac{x}{32}}{\frac{x}{32}+\frac{200}{20}}\times 25$
$\frac{1}{5}=\frac{\frac{x}{32}}{\frac{x}{32}+10}$
$\frac{1}{5}=\frac{x\times 32}{32(x+320)}$
$5x=x+320$
$4x=320$
$x=\frac{320}{4}=80gm$