Question

Sulphur pieces do not react with cold concentrated nitric acid. But sulphur powder reacts.
a) Explain the reason why the rate of chemical reaction is increased here?
b) Suppose you want to increase the rate of reaction again. Which way you would choose? Give reason.

Answer 1

a) Sulphur pieces do not react with cold concentrated nitric acid but sulphur powder reacts because when surface area increases rate of effective collision increases. So the rate of reaction increases.

b) If you want to increase the rate of reaction, you should heat the mixture.
When temperature increases more molecules will get threshold energy. So rate of effective collision and rate of reaction increases.