Question

An open vessel containing certain gas at $300K$ if the vessel is heated upto $400K$ , the the percent of mole of gas escaped out is ?

• A. $75$
• B. $50$
• C. $25$
• D. $20$

Answer 1

The correct option is C $25$

We know $PV=nRT$

$n_1=1,T_1=300K,T_2=400K,n_2=?$

$P_1{V}_1=n_{1}R{T}_1,P_2{V}_2=n_{2}R{T}_2$

$\Rightarrow \frac{n_1}{n_2}=\frac{T_2}{T_1}$

$\Rightarrow \frac{1}{n_2}=\frac{400}{300}$

$\Rightarrow n_2=\frac{3}{4}$ .

The fraction of air which goes out of the vessel= $1-\frac{3}{4}=\frac{1}{4}$.

Thus, the answer is $25$% .