What is Le Chatelier's principle? Discuss breifly the factors which can influcence the equilibrium.

Explanation

Le Chatelier.s Principle - Statement : "If a system at equilibrium is subjected to the change of un pressure, temperature (or) concentration, the system is shifted in such a way as to nullify the effect of change.
Explanation :
1) Concentration: Increase of reactant concentrations pushes the equilibrium state to the products side and increase of the reactions concentrations pushes to the equilibrium to the reactants side, For example in the chemical equilibrium.
`H_(2)(g)+I_(2)(g) hArr 2HI(g)`
Increases of `H_(2)` or `I_(2)` concentrations pushes the equilibrium in favours of HI and similarly the increase of HI concentrations pushes the equilibrium in favour of `H_(2) and I_(2)`
2) Pressure : Pressure will have no effect on the equilibrium reactions in which there is no change in the number of moles of the reactants and the products,
For example pressure will have no effect on sure will have no effect on
`H_(2)(g)+I_(2)(g) hArr 2HI(g)` equilibrium
(or) `N_(2)(g)+O_(2)(g) hArr 2NO(g)` equilibrium.
But in the case of reactions in which there is a change in the number of moles of the reactants and the products increase of pressure pushes the reaction equilibrium in the direction in which there is a decrease in the number of moles.
For example in the reaction `PCl_(s)(g) hArr PCl_(3)(g)+Cl_(2)(g)`
Increase of pressure favours the backward reaction `PCl_(3)(g)+Cl(g)+to Pcl_(5)(g)` and the decrease of pressure favour the forward reaction` PCl_(5)(g)to PCl_(3)(g)+Cl_(2) (g)`
3) Temperature : Increase of temperature favour the endothermic reaction and decrease of temperature favours.exothermic reactions.
For example.
`N_(2)(g)+O_(2)(g) hArr 2NO(g)-180.8 kJ`
Increase of temperature favours
The forward reaction
`N_(2)(g)+O_(2)(g) to 2NO(g)` since (exothermic)
decrease of temperature favour the dissociation of NO into `N_(2) and O_(2)` since it is exothermic,
The backward reaction
`2NO (g) to N_(2)(g)+O_(2)(g)` (since exothermic)