Дмитрий pH = 14 - pOH pOH = - lg[OH(-)] n(NaOH) = 4/40 = 0,1 моль C(NaOH) = 0,1/0,1 = 1 моль/литр [NaOH] = [OH(-)] = 0,1 pOH = -lg0,1 = 1 pH = 14-1 = 13