The volume of a given amount of gas at $27^{\circ} C$ at constant pressure is $420 \ cm^3$. If the temperature is reduced by $20^{\circ} C$ at constant pressure, what will be the volume of the gas (in $cm^3$)?

The densities of $2$ gases are in the ratio $1:2$ and their temperatures are in the ratio $2:1$. What is the ratio of their respective pressures?

$A$ $10 \, L$ cylinder contains $0.4 \, g$ of helium,$1.6 \, g$ of oxygen,and $1.4 \, g$ of nitrogen at $27 \, ^\circ C$. Calculate the total pressure of the mixture and the partial pressure of helium gas. Assume ideal gas behavior. $(R = 0.082 \, L \, atm \, K^{-1} \, mol^{-1})$

Calculate the volume in liters for $7 \ g$ of $O_2$ gas at $27 \ ^\circ C$ and $750 \ mm$ of $Hg$ pressure.

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

At $300 \, K$ constant temperature,a gas having $20 \, cm^3$ volume and $1 \, bar$ pressure is converted into $50 \, cm^3$. Calculate the final pressure. (in $, bar$)