$A$ cylinder of fixed capacity $67.2 \text{ litres}$ contains helium gas at $STP$. The amount of heat needed to raise the temperature of the gas in the cylinder by $20^{\circ} C$ is: (in $\text{ J}$)

Molar specific heat of oxygen at constant pressure $C_p = 7.2 \, cal/mol \cdot ^\circ C$ and $R = 8.3 \, J/mol \cdot K$. At constant volume,$5 \, mol$ of oxygen is heated from $10^\circ C$ to $20^\circ C$. The quantity of heat required is approximately ........ $cal$.

Given below are observations on molar specific heats at room temperature of some common gases.

Gas	Molar specific heat $(C_v)$ $(cal\, mol^{-1}\, K^{-1})$
Hydrogen	$4.87$
Nitrogen	$4.97$
Oxygen	$5.02$
Nitric oxide	$4.99$
Carbon monoxide	$5.01$
Chlorine	$6.17$

The measured molar specific heats of these gases are markedly different from those for monatomic gases. Typically,molar specific heat of a monatomic gas is $2.92 \; cal/mol\; K$. Explain this difference. What can you infer from the somewhat larger (than the rest) value for chlorine?

The molar specific heats of an ideal gas at constant pressure and constant volume are denoted by $C_p$ and $C_v$ respectively. If $\gamma = \frac{C_p}{C_v}$ and $R$ is the universal gas constant,then $C_v$ is equal to:

The amount of heat required to raise the temperature of $2$ moles of helium gas from $0^{\circ}C$ to $100^{\circ}C$ at constant volume and constant pressure,respectively,is:

$A$ diatomic gas molecule has translational,rotational,and vibrational degrees of freedom. The ratio ${C_P}/{C_V}$ is