One litre of oxygen at a pressure of $1 \,atm$ and two litres of nitrogen at a pressure of $0.5 \,atm$ are introduced into a vessel of volume $1 \,L$. If there is no change in temperature, the final pressure of the mixture of gas (in $atm$) is

$A$ 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 $RT$)

If $4$ moles of an ideal monoatomic gas at temperature $400 \,K$ is mixed with $2$ moles of another ideal monoatomic gas at temperature $700 \,K$, the temperature of the mixture is:

Two containers of equal volume contain identical gases at pressures $P_1$ and $P_2$ and absolute temperatures $T_1$ and $T_2$ respectively. The vessels are joined and the gas reaches a common pressure $P$ and a common temperature $T$. Then:

$A$ 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.