The density of a gas at $27\,^oC$ and $1\, atm$ is $d$. At constant pressure,at which of the following temperatures will its density become $0.75\, d$?

At $STP$,$2 \ mol$ of $N_2$ gas in a $50 \ L$ container exhibits:

An ideal gas $(X)$ present in a vessel of volume $V \ L$ exerted a pressure of $16.4 \ atm$ at $200 \ K$. What is its concentration in $mol \ L^{-1}$? (Given $R=0.082 \ L \ atm \ mol^{-1} \ K^{-1}$)

$A$ gas has a volume of $3.4 \ L$ at $298 \ K$. What is the final temperature if the volume of gas increases to $6.8 \ L$ (in $K$)?

Pressure of $1 \, g$ of an ideal gas $A$ at $27^{\circ} C$ is found to be $2 \, bar$. When $2 \, g$ of another ideal gas $B$ is introduced in the same flask at the same temperature,the pressure becomes $3 \, bar$. Find a relationship between their molecular masses.

The same gas is filled in two containers $X$ and $Y$. If the pressure,volume,and absolute temperature of the gas in container $X$ are three times those in container $Y$,and the mass of the gas in $X$ is $m \, g$,what will be the mass of the gas in $Y$?