Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride

Metal compound A reacts with dilute hydrochloric acid to produce effervescence. The gas evolved extinguishes a burning candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride.

Answer: Since CO₂ gas is liberated and the salt obtain has metal Ca, it implies the reactant metal compound shall be a carbonate i.e. CaCO₃ 
The chemical equation is:

    

CaCO₃ (s)   +  2HCl (aq)  →   CaCl₂ (s) + CO₂ (g) + H₂O (l)

Calcium Carbonate + Hydrochloric Acid  →  Calcium Chloride + Carbon Dioxide + Water