In which of the following conditions will the molar volume of $CO_2$ be maximum?

An ideal gas on isothermal reversible compression from $10 \ L$ to $5 \ L$ performs $1730 \ J$ of work at $300 \ K$. Calculate the number of moles of gas involved in the compression? $(R = 8.314 \ J \ K^{-1} \ mol^{-1})$

An ideal gas expands isothermally and reversibly from $10 \ m^{3}$ to $20 \ m^{3}$ at $300 \ K$ performing $5.187 \ kJ$ of work on surroundings. Calculate the number of moles of gas undergoing expansion? $(R = 8.314 \ J \ K^{-1} \ mol^{-1})$

At a given temperature,the density of gas $x$ is twice the density of gas $y$. If the molar mass of $y$ is three times the molar mass of $x$,find the ratio of their pressures $(P_x/P_y)$.

Calculate the weight of $CH_4$ in a $9 \ L$ cylinder at $16 \ atm$ and $27 \ ^\circ C$ in grams.

$A$ $10 \ g$ of a gas at atmospheric pressure is cooled from $273 \ ^oC$ to $0 \ ^oC$ keeping the volume constant,its pressure would become ............. $atm$.