大学化学 >> 2023, Vol. 38 >> Issue (11): 242-248.doi: 10.3866/PKU.DXHX202302039

师生笔谈 上一篇    下一篇

价层电子对互斥理论教学盲区与实践优化

刘宗怀(), 何学侠, 陈沛, 石峰   

  • 收稿日期:2023-02-16 录用日期:2023-03-27 发布日期:2023-05-22
  • 通讯作者: 刘宗怀 E-mail:zhliu@snnu.edu.cn
  • 基金资助:
    陕西师范大学一流课程无机化学教学资源建设(2021)

The Teaching Blind Spot and Practice Optimization of Valence Shell Electron Pair Repulsion Theory

Zonghuai Liu(), Xuexia He, Pei Chen, Feng Shi   

  • Received:2023-02-16 Accepted:2023-03-27 Published:2023-05-22
  • Contact: Zonghuai Liu E-mail:zhliu@snnu.edu.cn

摘要:

价层电子对互斥(VSEPR)理论是定性判断简单分子(或离子)空间构型及中心原子杂化方式的有效方法,是现代价键理论的重要组成部分。本文针对VSEPR理论教学中电子对相互排斥机理不易讲明,氧原子作为配位原子不提供价电子等假设难理解和VSEPR理论与杂化轨道理论区别不清晰等教学盲区,通过明确端位原子提供价电子数的规定本质,清楚O原子位置及成键类型对分子(或离子)结构影响和多重键对于分子(或离子)空间构型的影响以及将VSEPR理论教学内容置于杂化轨道理论之前等教学实践优化,实现了学生对VSEPR理论本质理解和对分子空间构型准确判断能力的提升。

关键词: 价层电子对互斥理论, 价层电子对, 分子空间构型, 无机化学, 教学优化

Abstract:

The valence shell electron pair repulsion (VSEPR) theory, an important part of the modern valence bond theory, can be used for qualitatively determining the spatial configuration of simple molecules (or ions) and the hybridization mode of central atoms. There are some blind spots in teaching the VSEPR theory, such as the unclear nature of the electron pair repulsion, the difficulty in understanding of the hypothesis that oxygen atoms do not provide valence electrons as coordination atoms, and the unclear difference between VSEPR theory and hybrid orbital theory. In the light of this, this paper shows some teaching optimization methods that improve students' understanding of the nature of VSEPR theory and the ability to accurately judge molecular spatial configurations by clarifying the regulatory nature of valence electrons provided by coordination (terminal) atoms, the impact of oxygen atom positions and bonding types on the molecular (or ion) structures, and the effect of multiple bonds on the molecular (or ion) spatial configurations, as well as by teaching the VSEPR theory prior to the hybrid orbital theory.

Key words: Valance shell electron pair repulsion theory, Valance shell electron pair, Molecular spatial configuration, Inorganic chemistry, Teaching optimization