The volume of a gas will be double of what it is at $0^{\circ}C$ (pressure remaining constant) at:

$A$ gas at absolute temperature $300\,K$ has pressure $P = 4 \times 10^{-10}\,N/m^2$. Given the Boltzmann constant $k = 1.38 \times 10^{-23}\,J/K$,the number of molecules per $cm^3$ is of the order of:

$A$ vessel contains $16 \,g$ of hydrogen and $128 \,g$ of oxygen at standard temperature and pressure $(STP)$. The volume of the vessel in $cm^{3}$ is:

$A$ closed hollow insulated cylinder is filled with gas at $0^{\circ} C$ and also contains an insulated piston of negligible weight and negligible thickness at the middle point. The gas in one side of the piston is heated to $100^{\circ} C$. If the piston moves $5 \,cm$, the total length of the hollow cylinder is: (in $\,cm$)

What is the ratio of the universal gas constant $(R)$ to the Avogadro number $(N_A)$?

The volume of a gas at $21^{\circ}C$ temperature and $768 \,mm$ pressure is $1 \,L$. If the density of the gas is $1.2 \,g/L$ at $NTP$,then its mass will be ..... $g$.