Find the solubility of MnS in neutral water in gm/l ? Ksp of MnS = 2.6 x 10-14.
Solution –
MnS ——-> Mn2+ + S2-
solubility of MnS = S mole / litre
[Mn2+ ] = S mole / litre
[S2- ] = S mole / litre
It is 1 : 1 type salt .so,
Ksp = S2
2.6 x 10-14 = S2
S = √ 2.6 x 10-14
S = 1.612 x 10-7 mole / litre
S in gm /litre = S ( mole/litre )x mol.wt.
mol.wt of MnS = 55 + 32 = 87
S in gm /litre = 1.612 x 10-7 x 87 =140.24 x 10-7
S = 1.40 x 10-5 gm /litre Ans.