At $N.T.P.$,$1 \text{ cm}^3$ of oxygen and $1 \text{ cm}^3$ of hydrogen are kept in different containers. Which will have a greater number of molecules?

The figure shows two flasks connected to each other. The volume of flask $1$ is twice that of flask $2$. The system is filled with an ideal gas at temperatures $100\,K$ and $200\,K$ respectively. If the mass of the gas in flask $1$ is $m$,what is the mass of the gas in flask $2$?

$A$ container holds $10 \ kg$ of gas at a pressure of $10^7 \ N/m^2$. How much gas in $kg$ must be removed so that the final pressure becomes $2.5 \times 10^6 \ N/m^2$? (Assume temperature remains constant.)

Which of the following graphs correctly represents the variation of $\beta = - \left( \frac{dV}{dP} \right)/V$ with $P$ for an ideal gas at constant temperature?

Three containers of the same volume contain three different gases. The masses of the molecules are $m_1, m_2$ and $m_3$ and the number of molecules in their respective containers are $N_1, N_2$ and $N_3$. The gas pressures in the containers are $P_1, P_2$ and $P_3$ respectively. All the gases are now mixed and put in one of the containers. The pressure $P$ of the mixture will be

Dry air at sea level contains $75.5\%\, N_2$ by mass. If the total atmospheric pressure is $1 \,atm$,the partial pressure of nitrogen is approximately $... \,atm$.