A solid, X, was added to an excess of the liquid Y. A colourless gas was evolved and a white precipitate formed. The precipitate was not X. What might X and Y be?
- AX: $\text{BaCO}_3$, Y: $\text{H}_2\text{O}$
- BX: $\text{Ca}$, Y: dilute $\text{H}_2\text{SO}_4$
- CX: $\text{Mg}$, Y: dilute $\text{H}_2\text{SO}_4$
- DX: $\text{SrCO}_3$, Y: dilute $\text{HCl}$