Question

Some chemicals are given in the box below. Find out the ​chemicals needed to prepare hydrogen in the laboratory. [2 marks]

Sulphuric acid, Hydrochloric acid, Sodium nitrate, Zinc, Potassium Permanganate, Ammonium Chloride, Water

Answer 1

$\bullet$ Hydrogen is produced when granulated zinc reacts with dilute hydrochloric acid or sulphuric acid. [0.5 marks]

$\bullet$ The reactions can be represented as:
$\bullet$ $\mathrm{Zn}\left(s\right)+2\mathrm{HCl}\left(\mathrm{aq}\right)\to {\mathrm{ZnCl}}_2\left(\mathrm{aq}\right)+H_2\left(g\right)$ [0.5 marks]
$\bullet$ $\mathrm{Zn}\left(s\right)+H_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)\to {\mathrm{ZnSO}}_4\left(\mathrm{aq}\right)+H_2\left(g\right)$[0.5 marks]

$\bullet$ From the supplied chemicals, sulphuric acid, hydrochloric acid, and zinc can be used to prepare hydrogen. [0.5 marks]