Surface Chemistry - Result Question 14
####14. Which of the following is not an example of heterogeneous catalytic reaction?
(2019 Main, 10 Jan I)
(a) Haber’s process
(b) Combustion of coal
(c) Hydrogenation of vegetable oils
(d) Ostwald’s process
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Answer:
Correct Answer: 14. (a)
Solution:
- In heterogeneous catalytic reactions, physical state of reactants and that of catalyst(s) used are different.
Haber’s process, hydrogenation of vegetable oils and Ostwald’s process all are heterogeneous process. Combustion of coal is not a heterogeneous catalytic reaction.
- In Haber’s process
$$ N _2(g)+3 H _2(g) \xrightarrow{Fe(s), Mo(s)} 2 NH _3(g) $$
- Hydrogenation of vegetable oils,
$$ \underset{\text { (Unsaturated) }}{\text { Vegetable oil }(l)} \xrightarrow[\text { or } Ni(s)]{\left[\left(Ph _3 P\right) _3 Rh\right] Cl} \operatorname{Vanaspati}(s) $$
- Ostwald’s process,
$$ 4 NH _3(g)+5 O _2(g) \xrightarrow[V _2 O _5(s)]{Pt(s)} 4 NO(g)+6 H _2 O(g) $$
- No catalyst is used in combustion of coal. The reaction is highly spontaneous in nature.
$$ \underset{\text { (Coal) }}{C}+O _2 \longrightarrow CO _2 $$
