Answer:
Due to addition of acidic or basic solution.
Step-by-step explanation:
Water equilibrium varies with pH because with the addition of acidic solution the pH of the solution decreases due to the presence of H+ ions which also increases the concentration of H+ ions in the water solution while on the other hand, by the addition of basic solution the pH of water increases due to the presence of OH- ions which also increases the concentration of OH- ions in the solution.