# How can the formation of a solution be exothermic or endothermic?

Mar 17, 2014

Let us make two solutions observe whether they are exothermic or endothermic.

1. Solution of Ammonium chloride in water:
(a) Take 100 ml of water in a beaker, record its temperature.This is called initial temperature.

(b) Dissolve 4 g of Ammonium chloride in 100 ml of water. Add Ammonium chloride, to water and stir it. Record the temperature of the solution. The temperature is called final temperature.

(c) In this experiment , you will observe that the temperature of the water will decrease ( final temperature < initial temperature). ammonium chloride when dissolves in water absorbs heat from the water, water loses heat and its temperature decreases. It is an endothermic process because salt absorbs heat from the surrounding water.

2. Solution of Sodium hydroxide in water:
(a) Take 100 ml of water in a beaker, record its temperature.This is called initial temperature.

(b) Dissolve 4 g of Sodium Hydroxide in 100 ml of water. Add Sodium Hydroxide, to water and stir it. Record the temperature of the solution. The temperature is called final temperature.

(c) In this experiment , you will observe that the temperature of the water will increase ( final temperature > initial temperature). Sodium Hydroxide when dissolves in water releases heat to the water, water gains heat and its temperature increases. It is an exothermic process because salt releases heat to the surrounding water.