The relation between internal energy $U$,pressure $P$,and volume $V$ for an ideal gas is given by $U = 2 + 2PV$. The gas is:

$A$ closed container contains a homogeneous mixture of two moles of an ideal monatomic gas $(\gamma=5/3)$ and one mole of an ideal diatomic gas $(\gamma=7/5)$. Here,$\gamma$ is the ratio of the specific heats at constant pressure and constant volume of an ideal gas. The gas mixture does a work of $66 \ J$ when heated at constant pressure. The change in its internal energy is . . . . . . $J$.

$A$ gas mixture consists of $16 \ g$ of helium and $16 \ g$ of oxygen. For this mixture,the ratio $C_P/C_V$ is equal to:

$22 \ g$ of carbon dioxide at $27^{\circ} C$ is mixed in a closed container with $16 \ g$ of oxygen at $37^{\circ} C$. If both gases are considered as ideal gases,then the temperature of the mixture is nearly: (in $^{\circ} C$)

$1 \, \text{mole}$ 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 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.)