何謂[離子積]? 點解水Kw=1×10^-14 就pH最多14?

pH is not at most 14 or at least 1, it can go beyond the scale according to the molarity and the type of acid u talking about. if u ahve 10M of HI, u can get to -1 or -2 pH. if there are more H+, there will be less OH-. thin of Kw being a value that shows the relationship between the concentration of H+ and OH- in any particular pH. the relationship simply is based on the concentration of H+ and OH- at pH 7.