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 ..... $g$.

$A$ pressure cooker contains air at $1$ atm and $30^\circ C$. If the safety valve of the cooker blows when the inside pressure $\ge 3$ atm,then the maximum temperature of the air inside the cooker can be .... $^\circ C$.

Pressure of an ideal gas,contained in a closed vessel,is increased by $0.4 \%$ when heated by $1^{\circ} C$. Its initial temperature must be

We have a sample of gas characterized by $P, V$ and $T$ and another sample of gas characterized by $2P, V/4$ and $2T$. What is the ratio of the number of molecules in the first and second samples (in $: 1$)?

$A$ vessel of volume $8 \, L$ contains an ideal gas at $300 \, K$ and $2 \, atm$ pressure. The gas is allowed to leak until the pressure becomes $125 \, kPa$. Calculate the number of moles that leaked out if the temperature remains constant.

Two vessels separately contain two ideal gases $A$ and $B$ at the same temperature. The pressure of $A$ is twice that of $B.$ Under such conditions,the density of $A$ is found to be $1.5$ times the density of $B.$ The ratio of the molecular weight of $A$ to that of $B$ is