$A$ gas of mass $m$ undergoes expansion at a constant pressure $P$,resulting in graph $D$. Which graph will be obtained if the same gas of mass $2m$ undergoes expansion at a pressure of $P/2$?

An air bubble of volume $1.0 \; cm^{3}$ rises from the bottom of a lake $40 \; m$ deep at a temperature of $12 \; ^{\circ}C$. To what volume (in $cm^{3}$) does it grow when it reaches the surface,which is at a temperature of $35 \; ^{\circ}C$?

An air bubble of volume $2.9 \ cm^3$ rises from the bottom of a swimming pool $5 \ m$ deep. At the bottom of the pool, the water temperature is $17^{\circ} C$. The volume of the bubble when it reaches the surface, where the water temperature is $27^{\circ} C$, is . . . . . . $cm^3$. ($g = 10 \ m/s^2$, density of water $\rho = 10^3 \ kg/m^3$, and $1 \ atm = 10^5 \ Pa$)

$A$ box contains $n$ molecules of a gas. How will the pressure of the gas be affected if the number of molecules is made $2n$?

For one gram mole of a gas,the value of $R$ in the equation $PV = RT$ is nearly ...... $cal/K$

State Gay-Lussac's Law of Gaseous Volumes.