According to Le Chatelier's principle, changes in pressure only affect the position of equilibrium in gaseous reactions if there is a difference in the total number of moles of gas between the reactant and product sides of the balanced chemical equation.

In the scenario described, there is "no change in volume in a gaseous reaction," which implies that the total number of moles of gaseous reactants is equal to the total number of moles of gaseous products. For example, H\(_2\)\(_{(g)}\) + I\(_2\)\(_{(g)}\) ⇌ 2HI\(_{(g)}\).

When the number of moles of gas is the same on both sides, both the forward and backward reaction rates increase or decrease equally in response to a pressure change, so the equilibrium position remains unchanged.