Question

A gas is heated at constant volume, temperature of gas becomes 4 times of initial value, then mean free path for molecules

• A. becomes half
• B. becomes double
• C. remains same
• D. becomes $\sqrt{2}$ times

Answer 1

The correct option is C remains same

The general formula for mean free path is:
$\lambda =\frac{RT}{\sqrt{2}\pi d^{2}NP}$
given that volume is constant.

By $PV=nRTP\propto T$
$\lambda \propto \frac{1}{\sqrt{2}\pi d^2{N}_A}$
where, $N_A$= Avogadro's number.
Hence mean free path remains same.