If the distance between molecules is doubled at a constant temperature,the pressure will become .......

Assertion $(A)$: The temperature of a gas is a result of the kinetic energy of its molecules.
Reason $(R)$: Due to kinetic energy,the molecules collide with each other to produce thermal energy.

The temperature of a gas is $-78^{\circ} C$ and the average translational kinetic energy of its molecules is $K$. The temperature at which the average translational kinetic energy of the molecules of the same gas becomes $2K$ is: (in $^{\circ} C$)

The kinetic energy of $1$ mole of $He$ gas at $27^{\circ}C$ is .... $J$.

The $rms$ speed of an ideal hydrogen gas molecule in a gas chamber at $0^{\circ}C$ is $3180 \ m/s$. What is the pressure of the hydrogen gas in atmospheres? (Given: Density of hydrogen gas $\rho = 8.99 \times 10^{-2} \ kg/m^3$,$1 \ atm = 1.01 \times 10^5 \ N/m^2$)

Number of molecules in a volume of $4\, cm^{3}$ of a perfect monoatomic gas at some temperature $T$ and at a pressure of $2\, cm$ of mercury is close to $?$
(Given,mean kinetic energy of a molecule (at $T$) is $4 \times 10^{-14}\, erg$,$g=980\, cm/s^{2}$,density of mercury $=13.6\, g/cm^{3}$)