在中学化学中可用观察法、奇偶数法和化合价法配平化学反应式。在大学化学中依据电荷守恒原理 ,可用氧化数法配平氧化还原反应式 ;依据电荷和质量守恒原理 ,可用离子 -电子法配平水溶液中的氧化还原反应式。前者要计算反应前后氧化剂和还原剂中被还原和被氧化元素的氧化数变化 In the middle school chemistry, the observation method, odd-even method and valence method can be used to balance the chemical reaction equation. In the university chemistry, based on the principle of conservation of charge, oxidation-reduction reaction can be equilibrated with oxidation number method; according to the principle of conservation of charge and mass, ion-electron method can be used to balance the redox reaction in aqueous solution. The former needs to calculate the oxidation number of the reduced and oxidized elements in the oxidant and reducing agent before and after the reaction.