Question

A gaseous mixture was prepared by taking equal mole of $CO$ and $N_2$. If the total pressure of the mixture was found $1$ atmosphere, the partial pressure of the nitrogen $\left(N_2\right)$ in the mixture is:

• A. $0.5$ atm
• B. $0.8atm$
• C. $0.9atm$
• D. $1atm$

Answer 1

The correct option is A $0.5$ atm

According to Dalton's Law of partial pressure.

The partial pressure of gas $\propto$ Mole fraction of gas ($X$ gas)

$X_{CO}=\frac{n_{CO}}{n_{CO}+n_{N_2}}=\frac{n_{CO}}{2n_{CO}}[\because n_{CO}=n_{N_2}]$

$⟹X_{CO}=\frac{1}{2}=0.5$

Partial pressure of $N_2=X_{N_2}\cdot P_T=[1-X_{CO}]\cdot P=[1-0.5]\times \left[1\right]=0.5$ $atm$