$2\, moles$ of helium gas is mixed with $3\, moles$ of hydrogen molecules (taken to be rigid). What is the molar specific heat of the mixture at constant volume in $J/mol\, K$? $(R = 8.3\, J/mol\, K)$

Two thermally insulated vessels $1$ and $2$ are filled with air at temperatures $T_1, T_2$,pressures $P_1, P_2$,and volumes $V_1, V_2$ respectively. If the valve connecting them is opened,what is the temperature of the equilibrium mixture?

Two non-reactive monoatomic ideal gases have their atomic masses in the ratio $2: 3$. The ratio of their partial pressures,when enclosed in a vessel kept at a constant temperature,is $4: 3$. The ratio of their densities is:

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:

The molar heat capacity of a mixture of two gases at constant volume is $13R/6$. The ratio of the number of moles of the first gas to the second is $1:2$. The respective gases may be:

If two moles of diatomic gas and one mole of monoatomic gas are mixed,then the ratio of specific heats $\gamma$ for the mixture is: