Question

How does equilibrium gets effected when pressure is decreased ??

Answer 1

We know that,
PV= nRT
Where, if T = constant then, P and V are inversly proportional so that decreasing pressure will increase the volume.
So, on decreasing the pressure the volume increases and so no. of moles of gas per unit volume decreases. Since. according to Le-chetlier's principle, the change in equilibrium shifts the equilibrium in such direction which minimizes the effect, so the reduction in pressure will shift the equilibrium in that direction where the no. of moles is larger.