一、问题的提出芳香烃教学中常以苯与甲苯、二甲苯分别和高锰酸钾酸性溶液混合振荡的实验来对比说明苯具有特殊的安定性,它不能使高锰酸钾酸性溶液褪色;甲苯、二甲苯比苯活泼,由于苯环与甲基的相互影响,甲基被活化而较易氧化,二者均可以使高锰酸钾酸性溶液褪色。对于这个重要演示实验的做法,人教版原高二化学统编教材第135面指出的是“把苯、甲苯、二甲苯各2 mL 分别注入3支试管,各加入3滴 KMnO_4酸性 First, the problem raised Aromatic hydrocarbon teaching often benzene and toluene, xylene and potassium permanganate acid solution mixed oscillation experiments to contrast that benzene has a special stability, it can not make potassium permanganate acid solution fade; toluene , Xylene than benzene lively, due to the interaction of benzene ring and methyl, methyl is activated and more easily oxidized, both of which can make potassium permanganate acidic solution fade. For this important demonstration experiment practice, the PEP teach the first 135 pages pointed out that ”benzene, toluene, xylene each 2 mL were injected into three tubes, each adding 3 drops of KMnO_4 acid