Question

The molar solubility of nickel(II) carbonate is 8.12×10-5 mol/L. Express the solubility in units of g/L and calculate the concentration of nickel in a saturated nickel(II) carbonate solution. Solubility of NiCO3 in grams per liter = g/L Concentration of Ni2+ ion in a saturated solution = mol/L

Answer 1

Answer:

a) S NiCO3 = 9.3686 E-3 g/L

b) [Ni2+] = 3.768 E-4 mol/L

Explanation:

a) S NiCO3 [=] g/L

∴ molar mass NiCO3 = 118.702 g/mol

⇒ S NiCO3 = (8.12 E-5 mol/L)*(118.702 g/mol) = 9.3686 E-3 g/L

b) [Ni2+] = ?

• NiCO3 ↔ Ni2+  +  CO32-

           S             S              S

 ∴ Ksp =[Ni2+]*[CO32-] = 1.42 E-7 (25°C)

⇒ Ksp = S*S = S² = 1.42 E-7

⇒ S = √1.42 E-7

⇒ S = 3.768 E-4 M