复杂氧化还原滴定结果计算的总电子得失守恒法

Method of Total Electrons Conversation in Calculation of Complex Redox Titration

对于复杂氧化还原滴定结果的计算,从氧化还原反应的本质——电子得失入手,提出了总电子得失守恒法,并通过实例加以运用说明。具体步骤为:首先写出反应方程式,无需配平;然后找出整个反应过程前后氧化数发生改变的氧化剂和还原剂,并标注其氧化数;最后根据氧化剂得电子总数与还原剂失电子总数相等的原则列等式并带入数据计算。该方法简单易懂,无需配平反应方程式,可以缩短解题时间,减少出错概率,并有助于强化学生对氧化还原滴定的定量依据——总电子得失守恒的理解。

In terms of the theory of oxidation and reduction reactions involving electron transfer, the method of total electrons conversation in the whole process was put forward and applied to calculate the result of complex redox titration. Firstly, write the unbalanced chemical reaction equations. Then, identify all the oxidants and reductants in the whole titration process and analyze their oxidation number. Finally, write the equation that the total number of electrons gained equals to that of lost, and take the data into equation. Due to the unbalanced the reaction equations, the method can shorten the calculation time and reduce the probability of making mistakes. It also helps students to understand and master the quantitative basis of redox titration, the conservation of total electrons.