What is the response of a reversible reaction system to counteract a decrease in pressure?

In a reversible reaction, changes in pressure affect the system's equilibrium position according to Le Chatelier's principle, which states that a system at equilibrium will adjust to counteract any changes imposed on it. When the pressure in a system decreases, the equilibrium shifts in such a way as to increase the pressure.

This is achieved by favoring the side of the reaction that produces more gas molecules. If one side of the reaction has more gas molecules than the other, shifting towards that side will increase the total number of gas molecules in the system, effectively raising the pressure back toward its original state.

For example, consider a reaction where the reactants produce three moles of gas and the products result in two moles of gas. If the pressure is decreased in this scenario, the system will shift towards the side with three moles of gas in order to increase the pressure again.

In contrast, favoring the side with fewer gas molecules would decrease the number of gas molecules, which would not effectively counteract a decrease in pressure. Hence, the correct understanding of how a reversible reaction system responds to a decrease in pressure aligns with the option that states the system favors the side with more gas molecules.