Question

Hydrochloric acid reacts with a metal X to form a gas Y which burns with a ‘pop’ sound. Sodium hydroxide solution also reacts with the same metal X (on heating) to form the same gas Y.

1. Name X and Y.
2. Write the chemical equation of the reaction of metal X with
   1. hydrochloric acid, and
   2. sodium hydroxide solution.

Answer 1

1. Metal X is zinc (Zn), and Y is hydrogen gas.
2. 1. \[\ce{Zn_{(s)} + 2HCl_{(aq)} -> ZnCl2_{(aq)} + H2_{(g)}}\]
   2. \[\ce{Zn_{(s)} + 2NaOH_{(aq)} -> Na2ZnO2_{(aq)} + H2_{(g)}}\]