Question

An open flask containing air is heated from $300\text{K}$ to $500\text{K}$. What percentage of air will be escaped to the atmosphere, if pressure is keeping constant?

• A. $80$
• B. $40$
• C. $60$
• D. $20$

Answer 1

The correct option is B $40$

Let the volume of the container $\left(V_1\right)=V$
According to the question $T_1=300\text{K}{T}_2=500\text{K}$
At constant pressure $V_1{T}_2=V_2{T}_1\Rightarrow V_2=\frac{V_1{T}_2}{T_1}=\frac{V\times 500}{300}=\frac{5V}{3}$
$\therefore$ Volume of air escaped $=\frac{5V}{3}-V=\frac{2V}{3}$
$\therefore$ Percentage of air escaped $=\frac{2V/3}{5V/3}\times 100=40\%$