$n$ moles of an ideal gas at temperature $T$ (in kelvin) occupy $V \ L$ of volume, exerting a pressure of $P$ atmospheres. What is the concentration (in $mol / L$)?

The mass of a gas in a container at $1 \, \text{atm}$ pressure and $200 \, K$ temperature is $3.2 \, g$. What will be the mass of the same gas in the same container at $500 \, K$ temperature and $10 \, \text{atm}$ pressure?

At $127 \, ^oC$ temperature,the volume of a gas is $3 \, L$. If the volume of the gas becomes half at constant pressure,calculate the final temperature in Kelvin. (in $, K$)

If the density of dioxygen gas at $STP$ is $1.43 \, g \, L^{-1}$,calculate its density at $17 \, ^\circ C$ and $800 \, torr$ pressure.

The density of methane is maximum under which conditions?

At $200 \ K$,an ideal gas $(X)$ present in a $1 \ L$ flask has a concentration of $1 \ mol \ L^{-1}$. At the same temperature,$0.1 \ mol$ of $X$ is added into the vessel. What is the final pressure of the gas in $atm$?
(Given $R = 0.082 \ L \ atm \ mol^{-1} \ K^{-1}$)