Question

Figure 10.2 shows the industrial preparation of nitric acid. [5 MARKS]

(a) What is the ratio of the reactants taken in the above process?
(b) Name the common name of this process.
(c) Name the catalyst used.
(d) Why should the gases entering the apparatus be pure?
(e) Where do they react? Also, give balanced reactions.

Answer 1

Each Part: 1 Mark

(a) The ratio is 10 vol. of air : 1 vol. of $N{H}_3$.
(b) The common name of the process is Ostwald's process.
(c) The catalyst used is platinum.
(d) Gases entering the apparatus must be pure as impurities poison the catalyst and decrease the efficiency.
(e) Reaction takes place as follows:
• Catalytic chamber $4N{H}_3+5O_2\stackrel{Pt{.800}^{\circ }C}{\to }4N{O}_3+6H_{2}O+Heat$
• Oxidation chamber $2NO+O_2\stackrel{{50}^{\circ }C}{\to }2N{O}_2$
• Absorption tower $4N{O}_2+2H_{2}O+O_2\to 4HN{O}_3$