Question

State Le Chatelier’s principle. Discuss the effect of change of concentration on the following reaction: H2(g) + I2(g) ⇌ 2HI(g)

Answer 1

Le Chatelier's principle is an observation about chemical equilibria of reactions. It states that changes in the temperature, pressure, volume, or concentration of a system will result in predictable and opposing changes in the system in order to achieve a new equilibrium state.

$H_2(g) + I_2(g) ⇌ 2HI(g)$

If the concentration of $H_2$ or $I_2$ is increased,the system will try to maintain the reaction at original position and the reaction will proceed forward forming $HI$ to decrease the concentration of the reactants.

If the concentration of the reactants is decreased,the reaction will tend to oppose this change by moving in reverse direction resulting in formation of $H_2$ and $I_2$ .