$A$ gas mixture consists of $2.0$ moles of oxygen and $4.0$ moles of neon at temperature $T$. Neglecting all vibrational modes, calculate the total internal energy of the system. (Oxygen has two rotational modes.) (in $RT$)

If $2 \text{ moles}$ of an ideal monoatomic gas at a temperature of $27^{\circ} C$ is mixed with $4 \text{ moles}$ of another ideal monoatomic gas at a temperature of $327^{\circ} C$,then the temperature of the mixture of the two gases is: (in $^{\circ} C$)

If three moles of monoatomic gas $\left(\gamma=\frac{5}{3}\right)$ is mixed with two moles of a diatomic gas $\left(\gamma=\frac{7}{5}\right)$,the value of adiabatic exponent $\gamma$ for the mixture is:

If a mixture of $28 \, g$ of Nitrogen $(N_2)$,$4 \, g$ of Hydrogen $(H_2)$,and $8 \, g$ of Helium $(He)$ is contained in a vessel at temperature $400 \, K$ and pressure $8.3 \times 10^5 \, Pa$,the density of the mixture will be:

$1 \, \text{mole}$ of a gas having $\gamma = \frac{7}{5}$ is mixed with $1 \, \text{mole}$ of a gas having $\gamma = \frac{4}{3}$. What will be the $\gamma$ for the mixture?

The volume $V$ of an enclosure contains a mixture of three gases: $16 \, g$ of oxygen,$28 \, g$ of nitrogen,and $44 \, g$ of carbon dioxide at absolute temperature $T$. Consider $R$ as the universal gas constant. The pressure of the mixture of gases is: