How does common ion effect influence the solubility of a sparingly soluble salt?
Answer and explanation
Correct answer: It decreases solubility
Consider a salt MX dissolving as MX(s) ⇌ M+ + X−. If a soluble electrolyte already supplies M+ or X−, the concentration of that ion increases. By Le Chatelier's principle, the dissolution equilibrium shifts to the left, so the salt dissolves less until the solubility-product condition is restored. The effect is not an increase or complete disappearance of solubility.
Frequently asked questions
What is the correct answer to this question?
It decreases solubility
Why is this the correct answer?
Consider a salt MX dissolving as MX(s) ⇌ M+ + X−. If a soluble electrolyte already supplies M+ or X−, the concentration of that ion increases. By Le Chatelier's principle, the dissolution equilibrium shifts to the left, so the salt dissolves less until the solubility-product condition is restored. The effect is not an increase or complete disappearance of solubility.
Which subject and chapter does this question cover?
This is a Class 11 Chemistry question. Chapter: Equilibrium. Topic: Solubility product and common ion effect.
