In the system  AB(s)  ⇌   A(g)  +  B(g), doubling the quantity of AB(s) would

AB(s)  ⇌   A(g)  +  B(g)Active mass for Solid = 1 unityKC=x. xAmount of AB(s) doesn't appear in KC,KPSo, no change in amount of A and B.