In the equation $PV = nRT$,which of the following is $NOT$ equal to the value of $R$?

Three bulbs are filled with $CH_4$,$CO_2$,and $Ne$ as shown in the picture. The bulbs are connected through pipes of zero volume. When the stopcocks are opened and the temperature is kept constant throughout,the pressure of the system is found to be $...... \ atm$. (Nearest integer)

$A$ monoatomic ideal gas,initially at temperature $T_1$,is enclosed in a cylinder fitted with a frictionless piston. The gas is allowed to expand adiabatically to a temperature $T_2$ by releasing the piston suddenly. $L_1$ and $L_2$ are the lengths of the gas columns before and after the expansion,respectively. The ratio $\frac{T_2}{T_1}$ is:

$4 \ g$ of an ideal gas occupies $5.6035 \ L$ of volume at $546 \ K$ and $2 \ atm$ pressure. What is its molecular weight?

The density of gas $A$ is twice that of gas $B$ at the same temperature. The molecular weight of gas $B$ is twice that of gas $A$. The ratio of the pressure of gas $A$ to gas $B$ will be:

One mole of an ideal gas occupies $12 \ L$ at $297^{\circ} C$. What is the pressure of the gas?