Equilibrium - 7, 17

Equilibrium requistes

1. has to be a reversible reaction
2. must occur in a closed system

4 key features of a reaction at equilibrium

1. forward & backward reactions occur at the same rate
2. concentration of reactant & product particles remain at equilibrium constant
3. requires a closed system where only energy can be transferred
4. no change in macroscopic properties e.g. pH, colour, pressure

if value of Kc is larger

forward reaction favoured

Le Chat Principle (3)

1. system tends to **reestablish equilibrium**
2. by **altering concentration**
3. to **minimise change**

If Reactants added

forward reaction will be favoured, Kc unchanged

Change to pressure

equilibrium shifts to the side with less particles

More pressure in the Haber Process

encourages forward reaction as particles are 4 : 2 causing equilibrium to move to the right

Lowering temperature in the Haber Process

encourages the forward reaction