Question

Write the equation for the action of heat on:
(i) ammonium chloride
(ii) ammonium nitrate
State, whether each reaction is an example of thermal dissociation or thermal decomposition.

Answer 1

(i) On heating, ammonium chloride decomposes into ammonia and hydrogen chloride gas as shown below.

${\mathrm{NH}}_4\mathrm{Cl}\left(\mathrm{s}\right)\stackrel{△}{\to }{\mathrm{NH}}_3\left(\mathrm{g}\right)+\mathrm{HCl}\left(\mathrm{g}\right)$

(ii) On heating, ammonium nitrate decomposes into water vapour and nitrous oxide as shown below.

${\mathrm{NH}}_4{\mathrm{NO}}_3\stackrel{△}{\to }{\mathrm{N}}_2\mathrm{O}+2{\mathrm{H}}_2\mathrm{O}$

Both reactions are examples of thermal decomposition.