Which of the following gases is least soluble in water at the same temperature and pressure?

If $CO_2$ gas having a partial pressure of $1.67 \ bar$ is bubbled through $1 \ L$ water at $298 \ K$,the amount of $CO_2$ dissolved in water in $g \ L^{-1}$ is approximately. (Henry's law constant of $CO_2$ is $1.67 \ kbar$ at $298 \ K$)

Consider a solution of $CO_{2(g)}$ dissolved in water in a closed container. Which one of the following plots correctly represents the variation of $log$ (partial pressure of $CO_2$ in vapour phase above water) [y-axis] with $log$ (mole fraction of $CO_2$ in water) [x-axis] at $25^{\circ}C$?

Solubility of a gas in a liquid increases with

Henry's law constants for $O_2$ and $N_2$ are $K_{O_2} = 3.3 \times 10^7 \ atm$ and $K_{N_2} = 6.51 \times 10^7 \ atm$. Calculate the ratio of $\frac{X_{O_2}}{X_{N_2}}$,i.e.,the ratio of mole fractions of $O_2$ and $N_2$ dissolved in water at $25 \ ^\circ C$ from air. (Assume air contains $20 \%$ $O_2$ and $80 \%$ $N_2$ by volume).

Identify a pair of gases from the following that does not obey Henry's law.