Chemistry
Chemistry
Problem
The three crystalline salts Mg(OH)(s), NaSO(s), and KHPO(s) are each sparingly soluble in water. Assume the temperature is 25 °C. (a) For each salt, predict whether raising the pH of the solution (i.e., making the solution more basic) will increase, decrease, or not change its molar solubility. Present your predictions in a clearly organized table. (b) For one salt whose solubility you predicted would decrease upon raising the pH, write the net ionic equation that accounts for this effect. (c) For one salt whose solubility you predicted would increase upon raising the pH, write the net ionic equation that accounts for this effect. (d) Briefly discuss why NaSO(s) behaves differently from the other two salts with respect to pH changes, citing pertinent acid–base properties of the constituent ions.Intuitive explanation
When a salt dissolves, it reaches an equilibrium between solid and dissolved ions—this is captured by the solubility product constant . The key insight is that each salt dissociates into a different number and type of ions, so you need to write the correct equilibrium expression for each one and use to relate solubility to ion concentrations. Understanding how many ions each formula unit produces will let you set up the math correctly.
Intuitive explanation
When a salt dissolves, it reaches an equilibrium between solid and dissolved ions—this is captured by the solubility product constant . The key insight is that each salt dissociates into a different number and type of ions, so you need to write the correct equilibrium expression for each one and use to relate solubility to ion concentrations. Understanding how many ions each formula unit produces will let you set up the math correctly.