对任何一个原子来说,其原子核所带的正电荷总是等于核外所带的负电荷,因而整个原子作为一个整体呈电中性;对于含有由多种原子组成的多种化合物的体系来说,一些原子得到的电子数必等于另一些原子失去的电子数以维持体系的电中性。这个原则在化学中已被广泛地应用,表现在: 1.用于求结构未知的化合物中某元素的氧化数。 For any atom, the positive charge carried by its nucleus is always equal to the negative charge carried by the nucleus, so that the entire atom is electrically neutral as a whole. For a system containing multiple compounds of many atoms Said that the number of electrons received by some atoms must be equal to the number of electrons lost by other atoms in order to maintain the neutrality of the system. This principle has been widely used in chemistry, manifested in: 1. For the unknown number of compounds of unknown oxidation number.