What is the effect of increasing the concentration of water in an equilibrium reaction?

Question

In an equilibrium reaction, if the products are aq ions and water, apparently when water is added the reaction will favour the left to decrease the conc of water. But since the conc of ions is decreasing, won't the equation favour the right to increase the conc of ions?

Can it be answered qualitatively, or does it depend on the individual concs?

Does it have something to do with the fact that the system is closed?

Answer 1

According to Le Chatelier's Law, if a system at equilibrium encounters any stress such as a change in concentration, temperature, or total pressure, it will adjust itself to counteract that change. So in your equilibrium system, there is water and aqueous ions in the products. If you add water to the system, it will shift to the left to produce more reactants and use up the extra water. This is because any time you add a substance to an equilibrium system, it shifts accordingly to use up the added substance and maintain the equilibrium. The system will shift to the right to produce more ions in addition to water only when ions are removed from the system. Then it will shift toward the products to replace the lost ions and maintain the equilibrium.

Answer 2

Yes, and according to how much you have. Kc drives the reaction for its face value in the way it should go initally