质量守恒定律是一条重要的基本规律,它反映了在发生化学反应时反应物与生成物之间的最根本的质量关系。在现行初中化学教科书上表述为:“参加化学反应的各物质的质量总和,等于反应后生成的各物质的质量总和。”在理解质量守恒定律时,首先,要注意适用范围是在发生化学反应中才成立,若发生象原子弹爆炸的核反应就不正确了,会有一定的质量损耗。 The law of conservation of mass is an important basic law, which reflects the most fundamental quality relationship between reactants and products in the occurrence of chemical reactions. In the current junior high school chemistry textbook, it states: “The sum of the mass of each substance participating in a chemical reaction is equal to the total mass of each substance produced after the reaction.” When understanding the law of conservation of mass, first of all, it should be noted that the scope of application is a chemical reaction. Only when China is established, if a nuclear reaction such as an atomic bomb explosion is not correct, there will be some quality loss.