Why phenolphthalein cannot be used to distinguish of NaCI and vinegar?
2007-01-11 15:05:22 · 1 個解答 · 發問者 2003 2 in 科學 ➔ 化學
phenolphthalein is pink when pH>8, since NaCl is neutral, pH=7, vinegar is acidic, pH<7, phenolphthalein is colourless at thses pH range.
用pH paper 就可以了
2007-01-11 15:11:20 · answer #1 · answered by Anonymous · 0⤊ 0⤋