1.同种元素发生氧化还原反应遵循哪些规律?(1)归中规律——同种元素发生氧化还原反应时价态归中。例如:1C+CO22CO22H2S+SO23S+2H2O32Fe3++Fe3Fe2+根据该规律可知,同种元素相邻价态之间不发生反应,如浓硫酸不能氧化二氧化硫,浓硝酸不能氧化二氧化氮。(2)歧化规律——同种元素发生氧化还原反应时,价态一部分升高一部分降低。例如:13NO2+H2O2HNO3+NO2Cl2+2NaOHNaCl+NaClO+H2O32Cu+Cu2++Cu 1. The same elements redox reactions occur following what rules? (1) Law of centralization - the same element redox reaction when the price of the return. For example: 1C + CO2  2CO22H2S + SO2  3S + 2H2O32Fe3 ++ Fe  3Fe2 + According to the law, the adjacent elements of the same species do not react between valence states, such as concentrated sulfuric acid can not be oxidized sulfur dioxide, concentrated Nitric acid can not oxidize nitrogen dioxide. (2) Disproportionate Law - When the same element redox reaction, the valence part of the increase is reduced. For example: 13NO2 + H2O2HNO3 + NO2Cl2 + 2NaOHNaCl + NaClO + H2O32Cu + Cu2 ++ Cu