Question

Calculate the pressure exerted by ${10}^{23}$, molecules each of mass ${10}^{-22}g$ in a container of volume $1/2$ the rms speed is ${10}^{5}cm{s}^{-1}$.

Answer 1

Using kinetic gas equation,
$P=\frac{1}{3}\frac{mn{c}^2}{V}$
Given, $V=1litre=1000mL=1000c{m}^3;n={10}^{23};m={10}^{-22}g$ and $c={10}^{5}cm{s}^{-1}$.
Substituting the values in the above equation,
$P=\frac{1}{3}\times \frac{{10}^{-22}\times {10}^{23}\times {10}^{10}}{1000}=3.333\times {10}^{7}dynec{m}^{-2}$.