Density of carbon monoxide is maximum at

If $20 \ cm^3$ of gas at $1 \ atm$ is expanded to $50 \ cm^3$ at constant $T$,what is the final pressure?

What is the compressibility factor of an ideal gas?

$A$ balloon contains $2.27 \ L$ of air and has a pressure of $1.013 \times 10^5 \ Nm^{-2}$. The balloon rises to a certain height and expands to a volume of $4540 \ mL$. What is the final pressure of air in the balloon?

What will be the effect on the density of $0.09 \ mol$ of a gas at $300 \ K$ if its pressure is increased?

When $2 \ g$ of a gaseous substance $A$ is introduced into an initially evacuated flask at $25^{\circ} C$,the pressure is found to be $1 \ atm$. $3 \ g$ of another gaseous substance $B$ is added to it at the same temperature and pressure. The final pressure is found to be $1.5 \ atm$. Assuming ideal gas behaviour,the ratio of molar masses of $A$ and $B$ is: