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一、基础知识梳理《烃》一章主要介绍了烷烃、烯烃、炔烃和芳香烃四类物质,其知识点较为琐碎,不易记忆。下面对此四类物质进行归类比较,方便学生记忆。烃的主要物理性质有:常温下,碳原子数≤4个的烃都是气态,碳原子数>4个的烃为液态或固态(新戊烷除外);同系物中随着碳原子数的增加,熔、沸点逐渐升高;碳原子数相同时,直链烃的熔、沸点高于带支链的烃。化学性质比较见下表:
First, the basic knowledge of combing “hydrocarbons” chapter mainly introduces four kinds of alkanes, alkenes, alkynes and aromatic hydrocarbons, the knowledge point is more trivial, not easy to remember. The following four categories of these substances are compared to facilitate student memory. The main physical properties of hydrocarbons are: at room temperature, the number of carbon atoms ≤ 4 hydrocarbons are gaseous, carbon atoms> 4 hydrocarbons are liquid or solid (neopentane excluded); homologues with the number of carbon atoms Increasing, melting, boiling point gradually increased; the same number of carbon atoms, straight chain melting, boiling point higher than branched hydrocarbons. Chemical properties compared to the table below: