In a thermally isolated system,two boxes filled with an ideal gas are connected by a valve. When the valve is in the closed position,the states of box $1$ and $2$ respectively are $(1 \, atm, V, T)$ and $(0.5 \, atm, 4V, T)$. When the valve is opened,the final pressure of the system is approximately ............... $atm$.

$A$ mixture of $2$ moles of oxygen and $4$ moles of argon is kept at temperature $T$. Neglecting all internal vibrations,the total internal energy of the system is: (in $, RT$)

$A$ 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 . . . . . . $J$.

$A$ mixture of two moles of hydrogen and one mole of argon gas is taken in a closed container at room temperature. Consider the following two statements:
$(i)$ The average kinetic energy of each molecule of $H_2$ and $Ar$ are the same.
$(ii)$ The partial pressure due to argon gas is more than that due to hydrogen gas.

$A$ gas mixture consists of $2$ moles of oxygen and $4$ moles of neon at temperature $T$. Neglecting all vibrational modes,the total internal energy of the system will be $...........\,RT$.

One gram mole of an ideal gas $A$ with the ratio of constant pressure and constant volume specific heats $\gamma_{A} = 5/3$ is mixed with $n$ gram moles of another ideal gas $B$ with $\gamma_{B} = 7/5$. If the $\gamma$ for the mixture is $19/13$,then what will be the value of $n$?