The endothermic and exothermic reactions should be identified. Note: if the forward reaction is endothermic, the reverse reaction will be exothermic with the same ΔH but opposite values.In this example: the forward reaction is endothermic, therefore the reverse reaction is exothermic. INCREASING THE TEMPERATURE-Increasing the temperature means there is more energy in the system (in the form of thermal energy).-Endothermic reaction is one where energy is absorbed from the surroundings.-Increasing temperature favours the endothermic reaction as the excess energy (from increasing the temperature) is absorbed, opposing the change brought about to the system. (Le Chatelier's principle)-Forward endothermic reaction is favoured meaning more of the right hand side products are made so the position of equilibrium moves to the right. DECREASING THE TEMPERATURE-Decreasing the temperature means there is less energy in the system (in the form of thermal energy).-Exothermic reacton is one where is energy is released to the surroundings. -Decreasing temperature favours the exothermic reaction in order to release more energy to the surrounding to oppose the change brought about to the system. -Reverse exothermic reaction is favoured meaning more of the left hand side reactants are made so the position of equilibrium moves to the left.