$A$ gas is present at a pressure of $2 \,atm$. What should be the increase in pressure, so that the volume of the gas can be decreased to $\frac{1}{4}$ of the initial volume at constant temperature (in $\,atm$)?

At $NTP$,$10 \ g$ of a gas occupies $5 \ L$ of volume. At what temperature will the volume become double for the same mass of gas at the same pressure?

$A$ weather balloon filled with hydrogen at $1 \, atm$ and $27 \, ^oC$ has a volume equal to $12000 \, L$. On ascending,it reaches a place where the temperature is $-23 \, ^oC$ and the pressure is $0.5 \, atm$. The volume of the balloon is .............. $L$.

Find the temperature in degree Celsius if volume and pressure of $2 \ mol$ ideal gas is $20 \ dm^3$ and $4.926 \ atm$ respectively. $(R = 0.0821 \ dm^3 \ atm \ K^{-1} \ mol^{-1})$

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 $R = 0.082 \ L \ atm \ mol^{-1} \ K^{-1}$)

Which relation represents the change in density of an ideal gas with changes in temperature and pressure?