An exothermic reaction which proceeds with decrease in volume will give maximum yield at high P and
low T. Since the reaction proceeds with decrease in volume, at high pressure, the equilibrium will shift in the forward direction which will reduce the effect of high temperature. The exothermic reaction proceeds with evolution of heat.
When temperature is low, the equilibrium will shift in the forward direction so as to reduce the effect of low temperature. Hence, under the conditions of low temperature and high pressure, the yield of the reaction will be maximum.