Q.

pH of a saturated solution of Ca(OH)2 is 9. The solubility product (Ksp) of Ca(OH)2 is             [2019]

1 0.5×10-10  
2 0.5×10-15  
3 0.25×10-10  
4 0.125×10-15  

Ans.

(2)

pH of the saturated solution of Ca(OH)2 = 9

  pOH of the saturated solution of Ca(OH)2=14-9=5

[OH-]=10-5      (pH+pOH=14)

Ca(OH)2Ca2++2OH-s2s12×10-510-5

Ksp=[Ca2+][OH-]2=[12×10-5][10-5]2

=0.5×10-15