Write a note on the effect of concentration on Le-Chatelier's principle.

Explanation

If a little `N_(2)` is added at equilibrium (in a closed vessel), the concentration of `N_(2)` increases. System tries to decrease its concentration by shifting the equilibrium to the right side. Similarly, addition of `H_(2)` also favours the forward reaction. On adding `N_(2)orH_(2),Q_(c)` decreases because `Q_(c)=([NH_(3)]^(2))/([N_(2)][H_(2)]^(3))`. If `Q_(c)ltK_(c)` forward reaction gets favoured.
If concentration of `NH_(3)` is increased, the system tries to decrease the concentration of `NH_(3)`. The reverse reaction is favoured, `Q_(c)=([NH_(3)]^(2))/([N_(2)][H_(2)]^(3))`. On adding `NH_(3)`, the value of reaction quotient increases. Since `Q_(c)gtK_(c)`, the reaction proceeds in the reverse direction.