NTA Abhyas NEET2020ChemistryIonic EquilibriumPractice
When solid lead iodide is added to water, the equilibrium concentration of I - becomes 2.6 × 1 0 - 3 M. What is the K s p for P b I 2 ?
Options
- A2.2 × 1 0 - 9
- B8.8 × 1 0 - 9
- C1.8 × 1 0 - 8
- D3.5 × 1 0 - 8
Correct answer
B. 8.8 × 1 0 - 9
Step-by-step solution
The equilibrium is P b I 2 ⇌ P b 2 + + 2 I - On the basis of this equation, the concentration of P b 2 + ions will be half of the concentration of I - ions. Thus, [ I - ] = 2.6 × 1 0 - 3 M and [ P b 2 + ] = 1.3 × 1 0 - 3 M K s p = [ P b 2 + ] [ I - ] 2 = [ 1.3 × 1 0 - 3 M ] [ 2.6 × 1 0 - 3 M ] 2 K s p = 8.8 × 1 0 - 9 .