$12\mathrm{.}11-2.$ Dissolving and Subsequent Crystallization. A batch of $1000kg$ of $KCl$ is

dissolved in sufficient water to make a saturated solution at $363K.$ where the

solubility is $35$ wt $\%$ KCl in water. The solution is cooled to $293K,$ at which

temperature its solubility is $25\mathrm{.}4wt\%.$