chemistry) a measurement of the level of acid or ALKALI in a solution or substance. In the pH range of 0 to 14 a reading of below 7 shows an acid and of above 7 shows an ALKALI: a pH of 7.5 8戒 发表于 6-9-2010 23:25
楼上是学化工专业的?我是精细化工专业的,不过是小中专。
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