Which of the following is a solution in which the physical states of solute and solvent are liquid and solid respectively?

Which among the following salts,solubility decreases with increase in temperature?

Solubility curves of four ionic salts $X$,$Y$,$Z$,and $W$ are given below. In which case is the value of $\Delta H_{sol.} < 0$?

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 $298 \ K$)

If the solubility of $H_2S$ in water at $STP$ is $0.195 \, m$,what is the value of $K_H$ in $bar$?

$CO_2$ gas is bubbled through water during a soft drink manufacturing process at $298 \ K$. If $CO_2$ exerts a partial pressure of $0.835 \ bar$,then $x \ mmol$ of $CO_2$ would dissolve in $0.9 \ L$ of water. The value of $x$ is $.....$ (Nearest integer).
(Henry's law constant for $CO_2$ at $298 \ K$ is $1.67 \times 10^3 \ bar$)