The following reaction is allowed to reach equilibrium. $$\text{CoBr}_2(g)\rightleftarrows\text{CO}(g)+\text{Br}_2(g)$$ What happens to the reaction when inert argon gas, $\text{Ar}(g)$, is added?
The solution to this problem states that the addition of an inert gas would not change the concentrations of the other gases, and therefore, the reaction is still at equilibrium.
However, won't adding the argon result in an increase in the pressure of the system, and, to restore the equilibrium, the number of molecules should be reduced and the reverse reaction would be favored? Can someone please explain?