PCl5(g) ↔ PCl3(g) + Cl2(g) In the reaction above, a decrease in pressure will

Answer Details

In the reaction above, a decrease in pressure will increase the yield of PCl3. This is because pressure and the direction of a reaction are related through Le Chatelier's Principle. According to this principle, if a stress is applied to a system at equilibrium, the system will respond in a way that tends to counteract the stress. In this case, the decrease in pressure is a stress applied to the system, and the system will respond by shifting the equilibrium to the side with the greater number of moles of gas, which is the side with PCl3 and Cl2. This shift will increase the yield of PCl3 and decrease the yield of PCl5.