Question

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. 

Answer 1

The divalent element M is Zn.
`Zn(S)+underset("Sodium hydroxide")(2Na_(2)ZnO_(2)(aq))+underset("Hydrogen")H_(2)uparrow`
`Zn(s)+underset("Dil. hydrichloric acid")(2HCl(aq))tounderset("Zinc chloride")(ZnCl__(2)(aq))+H_(2)uparrow`
The produced gas can be identified by briging a burning splinter near the gas (mouth of the reaction vessel). The gas burns with a pop sound, hence it is hydrogen.