A container of fixed volume has a mixture of one mole of hydrogen and one mole of helium in equilibrium at temperature T. Assuming that gases are ideal, the correct statement(s) is (are)

For the mixture equivalent degrees of freedom is calculated using the relation

$F_{eq}=\frac{n_1{f}_1+n_2{f}_2}{n_1+n_2}$

$f_{eq}=\frac{5+3}{2}=4$

$U=\frac{f}{2}nRT$

For mixture, $U=\frac{4}{2}nRT$

$\therefore$ Energy per mole: $\frac{U}{n}=2RT$

For mixture, $\gamma =1+\frac{2}{f}=1+\frac{1}{2}=\frac{3}{2}$

$M_{mix}=\frac{1\times 2+1\times 4}{2}=3$

${\gamma }_{He}=1+\frac{2}{3}=\frac{5}{3}$

Ratio of speed of sound = $\sqrt{\frac{{\gamma }_{mix}}{M_{mix}}\frac{M_{He}}{{\gamma }_{He}}}=\sqrt{\frac{6}{5}}$

$V_{ms}=\sqrt{\frac{3RT}{M}}ratio=\sqrt{\frac{2}{4}}=\frac{1}{\sqrt{2}}$