基于路易斯结构式的含氧酸酸性半定量判定方法:1/2规则

1/2 Rule:Semi Quantitative Determination Method for Acidity of Oxyacid Based on Lewis Structural Formula

基于经典价键理论中路易斯结构式建立了判定常见含氧酸酸性强弱的半定量方法"1/2规则",并利用密度泛函理论验证了方法的可靠性和可行性。该方法可以用于判定常见含氧酸的强弱,同时解释多元酸的逐级电离过程、同种元素不同价态含氧酸酸性强弱变化规律等。该方法有助于学生掌握各类含氧酸酸性的判定规律,改变现有机械记忆的学习方法,引导学生形成"结构-能量-性质"的化学学科基本逻辑体系,提升学生的"宏观辨识与微观探析"化学学科核心素养。

A semiquantitative method was constructed to compare and evaluate the acidity of oxoacids via the valence-bond-theory based Lewis structures, which was referred to as the "1/2 rule". Density functional theory calculations were performed to evaluate the reliability and feasibility of the "1/2 rule". The acidities of common oxoacids, stepwise ionization behavior of polyatomic acids, as well as the evolutionary tendencies of the oxoacids of multivalent elements, can be calculated with the constructed "1/2 rule". The students can understand the regularities of oxoacids by the introduction of the "1/2 rule". Therefore, rote-learning can be transformed into reasoning-understanding. Students can gradually dip into the chemical "structure-energy-property" logical system and understand the critical competence "macroscopic identification and microscopic reasoning" via the leaning of the "1/2 rule".