Question

Give balanced chemical equations for each of the following:
(i) Lab preparation of ammonia using an ammonium salt.
(ii) Reaction of ammonia with excess chlorine.
(iii) Reaction of ammonia with sulphuric acid.

Answer 1

The balanced chemical equations are:

(i) Lab preparation of ammonia $\left({\mathrm{NH}}_3\right)$ using an ammonium salt:

• Ammonium chloride $\left({\mathrm{NH}}_4\mathrm{Cl}\right)$ is used to make ammonia in the laboratory.
• $2{\mathrm{NH}}_4\mathrm{Cl}\left(\mathrm{aq}\right)+\mathrm{Ca}\left(\mathrm{OH}{)}_2\left(\mathrm{s}\right)\stackrel{\text{Heat}}{⟶}{\mathrm{CaCl}}_2\right(\mathrm{aq})+2{\mathrm{H}}_2\mathrm{O}(\mathrm{l})+2{\mathrm{NH}}_3(\mathrm{aq})\uparrow$

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(ii) Reaction of ammonia $\left({\mathrm{NH}}_3\right)$ with excess chlorine $\left({\mathrm{Cl}}_2\right)$:

• When the greenish yellow gas chlorine is consumed in excess, it interacts with the colorless gas ammonia to produce a yellow-colored explosive liquid nitrogen trichloride $\left({\mathrm{NCl}}_3\right)$.
• ${\mathrm{NH}}_3\left(\mathrm{g}\right)+3{\mathrm{Cl}}_2\left(\mathrm{g}\right)⟶{\mathrm{NCl}}_3\left(\mathrm{aq}\right)+3\mathrm{HCl}\left(\mathrm{g}\right)$

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(iii) Reaction of ammonia $\left({\mathrm{NH}}_3\right)$ with sulphuric acid $\left({\mathrm{H}}_2{\mathrm{SO}}_4\right)$:

• ${\mathrm{H}}_2{\mathrm{SO}}_4$ is an acid while ammonia is a base. As a result, a neutralization reaction occurs, and salt is generated.
• $2{\mathrm{NH}}_3\left(g\right)+{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)⟶{\left({\mathrm{NH}}_4\right)}_2{\mathrm{SO}}_4\left(\mathrm{s}\right)$