Question

in which step of the industrial preparation of sulphuric acid, is a catalyst used?

• A. Formation of $S{O}_2$
• B. Formation of $S{O}_3$
• C. Formation of oleum
• D. Dilution of oleum

Answer 1

The correct option is B

Formation of $S{O}_3$

Due to it’s reversible nature, the oxidation of $S{O}_2$ to $S{O}_3$ is very slow and hence, the rate determing step of the process. Due to this a catalyst is used to increase the speed of the reaction.