7.2.5

Change in conditions	Nature of the reaction at equilibrium	Effect on Kc	Effect on equilibrium to keep the Kc constant	Notes
Use in Haber Decreasing the pressure of a gaseous reaction	Increase in volume/pressure, when reactants react into product.	Decrease	Shift to the right to favour the product	You are changing the condition to go against the nature of the reaction at equilibrium so fewer products is produce and Kc decrease. The system then balances this out by shifting the equilibrium to the right to produce more products. This one is use in Haber process.
Use in Contact Increasing the pressure of a gaseous reaction	Decrease in volume/pressure, when reactants react into product.	Decrease	Shift to the right to favour the product	You are changing the condition to go against the nature of the reaction at equilibrium so fewer products is produce and Kc decrease. The system then balances this out by shifting the equilibrium to the right to produce more products. This one is use in Contact process.
Use in both Decreasing the temperature of an exothermic reaction	Exothermic when reactants react into product	Decrease	Shift to the right to favour the product	You are changing the condition to go against the nature of the reaction at equilibrium so fewer products is produce and Kc decrease. The system then balances this out by shifting the equilibrium to the right to produce more products. This one is use in Contact/Haber process.
Use in both Adding a catalyst	Doesn’t matter	No effect	No effect	Adding catalyst will increase the rate of reaction but make no effect to the equilibrium. However, both Contact/Haber process use catalyst since they lower the pressure so the collision frequency, KE of particle(less than Ea) and rate of reaction decrease. So they use catalyst to compensate.