A solution containing Mn2+, Fe2+, Zn2+ and Hg2+ with a molar concentration of 10-3 M each is treated with 10-16 M sulphide ion solution. Which ions will precipitate first if Ksp of MnS, FeS, ZnS and HgS are 10-15, 10-23, 10-20 and 10-54 respectively?

Question

A solution containing Mn2+, Fe2+, Zn2+ and Hg2+ with a molar concentration of 10-3 M each is treated with 10-16 M sulphide ion solution. Which ions will precipitate first if Ksp of MnS, FeS, ZnS and HgS are 10-15, 10-23, 10-20 and 10-54 respectively? (A) FeS (B) MnS (C) HgS (D) ZnS

Tardigrade Admin · Accepted Answer

M2++S2- → MS Lower the value of Ksp, lower will be solubility. Hence, HgS will precipitate first.

$F e S$

$M n S$

$H g S$

$Z n S$

$M^{2 +} + S^{2 -} \to MS$
Lower the value of $K_{s p}$ , lower will be solubility. Hence, $H g S$ will precipitate first.

Q. A solution containing Mn2+, Fe2+, Zn2+ and Hg2+ with a molar concentration of 10−3M each is treated with 10−16M sulphide ion solution. Which ions will precipitate first if Ksp​ of MnS, FeS, ZnS and HgS are 10−15, 10−23, 10−20 and 10−54 respectively?

FeS

MnS

HgS

ZnS

M2++S2−→MS Lower the value of Ksp​, lower will be solubility. Hence, HgS will precipitate first.

$F e S$

$M n S$

$H g S$

$Z n S$

$M^{2 +} + S^{2 -} \to MS$
Lower the value of $K_{s p}$ , lower will be solubility. Hence, $H g S$ will precipitate first.