Changing the concentration

In general, if you add more of a reactant or product to an equilibrium system, the reaction will shift to the other side to use it up. If you remove some reactant or product, the reaction shifts to that side in order to replace it. Suppose that you have the ammonia system at equilibrium, and you then put in some more nitrogen gas. To reestablish the equilibrium, the reaction shifts from the left to the right, using up some nitrogen and hydrogen, and forming more ammonia and heat.

The equilibrium has been reestablished. You have less hydrogen and more nitrogen, ammonia, and heat than you had before you added the additional nitrogen. The same thing would happen if you had a way of removing ammonia as it was formed. The right-hand side of the teeter-totter would again be lighter, and weight would be shifted to the right in order to reestablish the equilibrium. Again, more ammonia would be formed.