Question

Which of the following are exothermic processes?

1. Reaction of water with quick lime
2. Dilution of an acid
3. Evaporation of water
4.  Sublimation of camphor (crystals)

Options

• (i) and (ii)

• (ii) and (iii)

• (i) and (iv)

• (iii) and (iv)

Answer 1

(i) and (ii)

Explanation - 

When water is added to quick lime, they react vigorously to form lime water and an excess amount of heat is lost to the surrounding. In the same way reaction of an acid with water is also an example of a highly exothermic reaction. Whereas evaporation of water and sublimation of camphor both these process requires heat for them to proceed in the forward direction and hence are examples of endothermic reactions.

Hence, the correct answer is option 1.