$A$ vessel of volume $V$ contains a mixture of ideal gases at temperature $T$. The gas mixture contains $n_1, n_2$ and $n_3$ moles of three gases. Assuming an ideal gas system, the pressure of the mixture is

$A$ container of fixed volume has a mixture of one mole of hydrogen and one mole of helium in equilibrium at temperature $T$. Assuming the gases are ideal,the correct statement$(s)$ is(are):
$(A)$ The average energy per mole of the gas mixture is $2RT$.
$(B)$ The ratio of speed of sound in the gas mixture to that in helium gas is $\sqrt{6/5}$.
$(C)$ The ratio of the rms speed of helium atoms to that of hydrogen molecules is $1/2$.
$(D)$ The ratio of the rms speed of helium atoms to that of hydrogen molecules is $1/\sqrt{2}$.

The capacity of a vessel is $3 \, L$. It contains a mixture of $6 \, g$ oxygen,$8 \, g$ nitrogen,and $5 \, g$ $CO_2$ at $27^{\circ}C$. If $R = 8.31 \, J/(mol \cdot K)$,then the pressure in the vessel in $N/m^2$ will be (approx.)

$A$ container has two chambers of volumes $V_1=2 \ L$ and $V_2=3 \ L$ separated by a partition made of a thermal insulator. The chambers contain $n_1=5$ and $n_2=4$ moles of an ideal gas at pressures $p_1=1 \ atm$ and $p_2=2 \ atm$,respectively. When the partition is removed,the mixture attains an equilibrium pressure of: (in $atm$)

$A$ 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 $RT$)

$N_1$ molecules of a gas at temperature $T_1$ are mixed with $N_2$ molecules at temperature $T_2$. The resulting temperature of the mixture gas is