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:

Metal compound A is CaCO₃

The Gas evolved is CO₂

The gas thus formed is an effervescent carbon dioxide gas when calcium carbonate reacts with hydrochloric acid. The carbon dioxide gas also acts as an extinguisher for fires. Hence, the burning candle is extinguished. The metal compound A, therefore, constitutes calcium carbonate.

The balanced equation of the reaction is

CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O