Iqbal treated a lustrous, divalent element M with sodium hydroxide. He observed the formation ,of bubbles in reaction mixture. He made the same observations when this element was treated with hydrochloric acid. Suggest how can he identify the produced gas. Write chemical equations for both the reactions. 

Explanation

The divalent element M is a metal. It reacts with both sodium hydroxide (alkali) and dilute hydrochloric acid to evolve hydrogen gas
`M(s) + 2NaOH(aq) rarrNa_(2)MO_(2)(aq) + H_(2)(g)`
`M(s) + 2HCl(aq) rarrMCl_(2)(aq) + H_(2)(g)`