An indicator that iseither a weak base or a weak acid andwhose dissociated and undissociated formsdiffer markedly in color. The color changemust occur within a narrow pH range. Ex-amples are methyl orange and phenol-phthalein.一種為弱酸或弱堿的指示劑。其解離和未解離狀態(tài)的顏色有......(本文共 250 字) [閱讀本文] >>