Question

following balanced chemical
reaction:
Ca2+
(aq)+ CO3
2--
(aq) ⇄CaCO3(S)
The amount of dissolved CaCO3 can be
increased on adding: CaCO3(S)
KNO3(S)
Na2CO3(S)
CH3COOH(S)

Answer 1

According to Le Chatelier's principle, When any system at equilibrium is subjected to change in concentration, temperature, volume or pressure , then the system readjusts itself to counteract (partially) the effect of the applied change and a new equilibrium is established.

Thus, upon increasing of the concentration of the reactants, the equilibrium will be shifted to the side of product formation and vice versa.

The answer is - CaCO3.