化学反应的实质是化学键的断裂和形成,表现为反应物原子之间的重新组合(生成新物质),而原子的种类和数目均不发生变化,这就是用守恒法解题的理论依据。一、得失电子守恒例1等物质的量的主族金属A、B、C分别与足量的稀盐酸反应,所得氢气的体积依次为VA、VB、VC,已知VB=2VC,且VA= The essence of the chemical reaction is the breakage and formation of chemical bonds, represented by the recombination of the atoms of the reactants (generation of new substances), and the type and number of atoms are not changed. This is the theoretical basis for solving the problem with the conservation method. First, the gain and loss of electron conservation Example 1 The amount of the main group of metals A, B, C were reacted with a sufficient amount of dilute hydrochloric acid, the resulting hydrogen volume followed by VA, VB, VC, known VB = 2VC, and VA =