1. Addition of which of the following will increase the solubility of CaCO3 in water? Consider the equilibrium process:

CaCO3 (s) Ca2 + (aq) + CO32 - (aq)

Carefully consider common ions, and whether any species present in solution can react with the additives.

Select all that apply.

Group of answer choices:

a. Na2CO3

b. HCl

c. NaHSO4

Answer: HCl

Explanation:

calcium carbonate dissolves in HCl acid producing CO 2 gas. It will not dissolve in pure water. The Ksp for calcium carbonate in water is 3.4 x 10-9 moldm-3 which is very low. What takes place here is actually a chemical reaction:

CaCO 3 (s) + 2HCl (aq) → CaCl 2 (aq) + H 2CO 3 (aq)

This reaction accounts for the solubility of the Calcium carbonate in HCl and not in pure water.