The total internal energy of $2$ moles of a monatomic gas at a temperature $27^{\circ} C$ is $U$. The total internal energy of $3$ moles of a diatomic gas at a temperature $127^{\circ} C$ is:

An oxygen cylinder of volume $30 \ L$ has $18.20 \ \text{moles}$ of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to $11 \ \text{atm}$ at a temperature of $27^{\circ} \text{C}$. The mass of the oxygen withdrawn from the cylinder is nearly equal to (Given: $R = \frac{100}{12} \ \text{J mol}^{-1} \text{K}^{-1}$, molecular mass of $O_2 = 32 \ \text{g/mol}$, $1 \ \text{atm} = 1.01 \times 10^5 \ \text{Pa}$) (in $\text{kg}$)

Nitrogen gas is filled in an insulated container. If $\alpha$ fraction of moles dissociates without exchange of any energy,then the fractional change in its temperature is ..............

One mole of an ideal gas undergoes a linear process as shown in the figure below. Its temperature expressed as a function of volume $V$ is

An ideal gas expands adiabatically $(\gamma = 1.5)$. To reduce the root-mean-square (r.m.s.) velocity of the molecules $3$ times, the gas has to be expanded by a factor of: (in $\times$)

Explain why:
$(a)$ there is no atmosphere on the Moon.
$(b)$ there is a fall in temperature with altitude.