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:
The gas CO 2 (Carbon Dioxide) produces (effervescence). It is used to extinguish fires, hence it extinguishes a burning candle.
We know that a metal compound reacts with acid to produce Salt, Carbon Dioxide and Water.
The reaction of metal compound ‘A’ and HCl can be written as,
A + HCl → CaCl 2 + CO 2 + H 2 O
The salt in a metal compound and acid reaction is formed by,Cation from metal compound and Anion from the acid.Therefore in this reaction:
Salt - CaCl 2
Cation - Ca 2+
Anion - Cl -
Hence, the metal compound A must have the Anion Ca 2+ . Therefore the metal Compound ‘A’ can be Calcium Carbonate (CaCO 3 ). The reaction hence becomes:
CaCO 3 + 2HCl → CaCl 2 + CO 2 + H 2 O