Question

A closed vessel contains $8\text{g}$ of oxygen and $7\text{g}$ of nitrogen. The total pressure is $10$ atm at a given temperature. If now, oxygen is absorbed by introducing a suitable absorbent, the pressure of the remaining gas in atm will be

• A. $2$
• B. $10$
• C. $4$
• D. $5$

Answer 1

The correct option is D $5$

$P_{O_2}V=n_{O_2}RT$ ...(i)

$P_{N_2}V=n_{N_2}RT$ ...(ii)

Dividing (i) by (ii) we get

$\frac{P_{0_2}}{P_{N_2}}=\frac{n_{0_2}}{n_{n_2}}=\frac{1/2}{1/2}=1$

5 atm is due to nitrogen and 5 atm due to oxygen. So, if we remove oxygen the pressure of remaining gas is 5 atm.