Q.

Lechatlier’s principle : If chemical reaction at equilibrium is subjected to change in temperature, pressure and concentration the equilibrium position shifts in the direction in which this change is reduced.
Factors effecting the equilibrium position
a) Concentration : Increases in the concentration of reactants favours the forward reaction. Increase in the concentration of products favours the backward reaction.
b) Pressure : Increase in the pressure favours that reaction in which volume decreases. Decrease in the pressure favours that reaction in which volume increases.
c) Temperature : Increase in temperature favours endothermic reaction and decrease in temperature favours exothermic reaction.