(1) After adding acid, the ionization degree of CH3COOH decreases, and so does c(CH3COOH). Because the concentration is given, HCl is added in the form of solution. We assume that 1mol/L acetic acid is added instead of HCl. Obviously, the ionization degree and c (CH3COOH) of ch3cooh will not change. But now the strong acid HCl is added, so the H+ concentration of the added acid is greater than that of the acetic acid, so it will inhibit the ionization of the original acetic acid. However, due to the increase of solution volume (regardless of volume effect), the solute CH3COOH will not increase, and c(CH3COOH) will inevitably decrease.

(2) In neutral solution, both c(H+) and c(OH-) are 10(-7). If H+ is consumed by hydrolysis, it will promote the ionization of water, but according to Le Chatelet's principle, the promoted part cannot offset the consumption, so c(H+) will be smaller than the original one. If the temperature is constant, the ionic product of water is 10(- 14), and c(H+) decreases, then c(OH-) will increase accordingly. If calculated according to sum, it should be larger than the original (mathematically, if both A and B are positive, the product of ab is constant, and a+b takes the minimum value if and only if a=b). (H+)(OH-) should be the same as c(H+)c(OH-).