Question

Addition of which of the following substances will increase the solubility of CuCO3 (s) in water ?

CuCO3 ---- Cu^2+ (aq) +2 CO3^2- (aq)

1. Aqueous hydrochloric acid
2. Aqueous sodium carbonate
3. Solid copper (II) carbonate

a) 1 only
b) 2 only
c) 3 only
d) 1 and 3 only
e) 1,2 and 3 only

Answer 1

You haven't written the correct equation. It should be
CuCO3(s) ==> Cu^2+(aq) + CO3^2-(aq)

I'll give you a couple of hints.
Adding HCl will react with CO3^2- to form H2O and CO2, thus decreasing CO3^2-. Remember Le Chatelier's Principle--decreasing CO3^2- will drive the reaction which way?

Adding Na2CO3 will increase (CO3^2-). Which way will that drive the reaction.

Adding solid CuCO3. You already have solid CuCO3 present; adding more will have no effect.

Answer 2

2 only

Answer 3

1 only

Answer 4

1 only