$A$ cylinder consists of a gas mixture of helium and oxygen. If the mass of helium is $4 \,g$ and the mass of oxygen is $32 \,g$, then the ratio of specific heat of the mixture $\left(C_p / C_V\right)$ is:

Two gases have temperature $T$,pressure $P$,and volume $V$ each. If they are mixed in a container of volume $V$ at the same temperature $T$,what will be the new pressure and mass of the mixture?

Four moles of hydrogen,two moles of helium,and one mole of water vapour form an ideal gas mixture. What is the molar specific heat at constant pressure of the mixture?

$A$ gas mixture consists of $8$ moles of argon and $6$ moles of oxygen at temperature $T$. Neglecting all vibrational modes,the total internal energy of the system is (in $RT$)

$A$ gaseous mixture consists of $2$ moles of oxygen and $4$ moles of argon at an absolute temperature $T$. Neglecting all vibrational modes,the total internal energy of the mixture of the gases is (in $RT$)

$A$ mixture of $7 \, g$ of nitrogen and $11 \, g$ of carbon dioxide is kept in a container at a temperature of $T = 290 \, K$. If the pressure of the mixture is $1 \, atm$ $(1.01 \times 10^5 \, N/m^2)$,then the density of the mixture is approximately . . . . . . $kg/m^3$.