给定分子式写所有同分异构体的结构简式,学生素有训练。近年高考卷中屡屡出现限定条件写出其几种或一种同分异构体的试题,由于解答时要运用收敛思维、递向思维,难度大大增加。现举几例进行归类分析。 Given a molecular formula to write all structural isoforms of isomers, students are trained. In recent college entrance examination papers, there have been repeated limited conditions to write out test questions of several kinds or isomers. Since the answer is to use convergent thinking and forward thinking, the difficulty is greatly increased. Here are some examples of classification analysis.