Question

An open vessel at $300K$ is heated till $\frac{2}{5}$ of the air in it expelled. Assuming that the volume of the vessel remains constant, the temperature to which the vessel is heated, is

• A. $750K$
• B. $400K$
• C. $500K$
• D. $1500K$

Answer 1

The correct option is C $500K$

We know at constant V and P:

$n_1{T}_1=n_2{T}_2\text{[}\because P_1{V}_1\text{constant ]}$

$n_1=n$ and $n_2=n-\frac{2n}{5}$ and $T_1=300K$

$n\left(300\right)=(n-\frac{2}{5}n)\left(T_2\right)=\left(\frac{3n}{5}\right)T_2$

$T_2=500K$