The volume of $2.8 \ g$ of $CO$ at $27^{\circ} C$ and $0.821 \ atm$ pressure is (Given: $R = 0.08210 \ L \ atm \ K^{-1} \ mol^{-1}$) (in $L$)

$A$ sample of gas occupies $100 \ mL$ at $27 \ ^oC$ and $740 \ mm$ pressure. When its volume is changed to $80 \ mL$ at $740 \ mm$ pressure,the temperature of the gas will be ............. $^oC$

$A$ $10 \, L$ 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. $(R = 0.082 \, L \, atm \, K^{-1} \, mol^{-1})$

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

Which one of the following is the correct $PV$ vs $P$ plot at constant temperature for an ideal gas? ($P$ and $V$ stand for pressure and volume of the gas respectively)

Explain the mathematical formula,graph,and absolute zero temperature for Charles' Law.