What is the density of carbon monoxide at $STP$ in $g \, L^{-1}$?

One mole of an ideal gas occupies $12 \ L$ at $297^{\circ} C$. What is the pressure of the gas?

At $21\, ^oC$ temperature,the volume of $212\, g$ of $O_2$ gas is $34\, dm^3$. If the pressure of the gas becomes $1.24\, bar$,then how many grams of $O_2$ gas are left in the container? $(R = 0.083\, dm^3\, bar\, K^{-1}\, mol^{-1})$

Which of the following expressions at constant pressure represents Charles's law?

What will be the pressure exerted by a mixture of $3.2 \ g$ of methane and $4.4 \ g$ of carbon dioxide contained in a $9 \ dm^3$ flask at $27^{\circ} C$?

The density of a gas at $-23 \ ^oC$ temperature and $780 \ \text{torr}$ pressure is $1.40 \ g/L$. Identify the gas.