What occurs when the pressure of a gaseous system at equilibrium is decreased?

When the pressure of a gaseous system at equilibrium is decreased, the equilibrium position shifts towards the side with more gas molecules. This behavior is rooted in Le Chatelier's Principle, which states that if a system at equilibrium experiences a change in conditions (such as pressure), it will respond in a way that counteracts that change.

In the case of pressure changes, the system will adjust the position of equilibrium to increase the pressure. If the pressure is decreased, the equilibrium will shift toward the side of the reaction that has more gas molecules. This shift helps to restore some of the lost pressure by increasing the total volume of gas produced in the reaction, as moving towards a side with more gaseous molecules results in a greater number of moles and subsequently higher pressure.

It is important to recognize that if the reactants and products have the same number of gas molecules, the change in pressure would not significantly impact the equilibrium position, leading to no change in the equilibrium. However, the provided answer aligns with systems where such a difference in gas molecule count exists.