Which of the following ionic solids exhibits a decrease in its solubility in water with an increase in temperature?

The $K_H$ values (in $k\text{bar}$) of argon $(I)$,carbon dioxide $(II)$,formaldehyde $(III)$,and methane $(IV)$ are $40.3$,$1.67$,$1.83 \times 10^{-5}$,and $0.413$ respectively at $298 \ K$. The increasing order of solubility of these gases in liquid is:

For the solution of the gases $w$,$x$,$y$ and $z$ in water at $298 \ K$,the Henry's law constants $(K_H)$ are $0.5$,$2$,$35$ and $40 \ kbar$,respectively. The correct plot for the given data is

Which of the following statements is correct regarding Henry's law?

Explain the equilibrium in soda water and explain it using Henry's law.

At $298 \ K$,how many millimoles of $CO_2$ gas will dissolve in $900 \ mL$ of water when $CO_2$ gas is passed through it? The $K_H$ value is $6.02 \times 10^{-4} \ bar$ and the partial pressure of $CO_2$ gas is $2 \times 10^{-8} \ bar$.