Question

Equal masses of $SO_2,CH_4$ and $0_2$ are mixed in empty container at 298 K, when total pressure is 2.1 atm. The partial pressure of $CH_4$ in the mixture is

• A. 0.5 atm
• B. 0.75 atm
• C. 1.2 atm
• D. 0.6 atm

Answer 1

Answer: (C)

1.2 atm

Answer 2

Molecular masses of $SO_2, CH_4$ and $O_2$ are 64, 16 and 32. Let mass of each gas taken = 64 g $n_{SO_2}= \frac{64}{64}$ = 1 . $n_{CH_4} = \frac{64}{16} = 4$ $n_{O_2} = \frac{64}{32} = 2$ $x_{O_2} = \frac{2}{7} : p_{O_2} = x_{O_2} \, P_{Total}$ = $\frac{2}{7} \times 2.1$ atm = 1.2 atm