Effect of volume in reaction

[noree_jauregui]

There was a worksheet that gave the reaction 2SO2(g)+O2(g)⇌2SO3(g). The question asked if the volume of the reaction container is reduced, will it favor the forward or reverse reaction? I predicted that it would favor the forward reaction to produce products because there are fewer moles of products. However, the answer states that volume will not affect the reaction. Why could this be? I know that pressure would favor the products in this case, but why wouldn't the volume have the same effect?

[Alex 3C]

Hi, I'm pretty sure that you are correct. Since there are 3 moles on the left and two on the right, it should proceed that if the volume were to decrease then the forward reaction would be favored.

[Bryan Lee 2L]

I think there is an error on the worksheet because there are 3 moles of gas on the reactant side compared to 2 moles of gas on the product side. Therefore, a decrease in volume would indeed favor the forward reaction (product side) to counteract the "stress". In this case, favoring the forward reaction would decrease pressure.