Q. A container of volume $30$ litre is filled with an ideal gas at one atoms pressure and $0^{\circ} C$ temperature. Keeping the temperature constant some mass of gas is allowed to escape from the container. Due to this the pressure of the gas decreases to $0.78$ atoms from the previous one. If the density of the gas at $N.T.P$. is $1.3\, gm /$ litre, find the mass (in gram) of the gas remaining.
Kinetic Theory
Solution: