Five moles of helium are mixed with two moles of hydrogen to form a mixture. Take molar mass of helium $M_1 = 4 \ g/mol$ and that of hydrogen $M_2 = 2 \ g/mol$. The equivalent molar mass of the mixture is:

$2 \text{ mole}$ of $N_2$ gas at $27 \, ^oC$ is mixed with $1 \text{ mole}$ of $He$ gas at $-73 \, ^oC$. Find the final temperature $T_{\text{mix}}$ of the mixture.

$A$ gaseous mixture has $2$ moles of oxygen and $4$ moles of Argon at a temperature $T$. Neglecting all vibrational modes of the molecules,the total internal energy of the system is ($R$ = Universal gas constant). (in $RT$)

Two ideal gases $A$ and $B$ having the same temperature $T$,same pressure $P$,and same volume $V$,are mixed together. If the temperature of the mixture is kept constant and the volume occupied by the mixture is reduced to $\frac{V}{2}$,then the pressure of the mixture will become:

One mole of monoatomic gas and three moles of diatomic gas are put together in a container. The molar specific heat (in $J\,K^{-1}\,mol^{-1}$) at constant volume is $(R = 8.3\,J\,K^{-1}\,mol^{-1})$.

Five moles of helium are mixed with two moles of hydrogen to form a mixture. Take molar mass of helium $M_1=4 \ g$ and that of hydrogen $M_2=2 \ g$. The equivalent degree of freedom $f$ of the mixture is: