氧化还原规律2（Oxidation reduction law 2）.docVIP

氧化还原规律2（Oxidation reduction law 2） Two. [basic knowledge of this section] 1, the law of determining the nature of valence 2, the strong generation of the law of the weak 3, the law of transformation of adjacent valence states 4, the strong reaction priority rule 5, the law of conservation of electronic gains and losses Three [key breakthroughs] (1) the law determining the nature of valence states Law： When the elements with variable valency, generally at the highest valence only with oxidation, the lowest valence only with the original, in the intermediate valence both with oxidative and reductive, but mainly for one. Application: Judging whether or not the elements or substances are oxidizing or reducible Such as: H2SO4 of concentrated S is at the highest price, only oxidation, S in H2S is at the lowest price, only reducible, S and SO2 in S are in the middle valence state, both oxidation and reduction. [1] please tell the following examples of several problems is wrong: H2S is reducible only The metal element has both oxidation and reduction The oxidation and reducibility of elements or substances depend not only on the valence states of the elements, but also on the concentrations, acidity, and temperature [example 2] Of the following groups of substances, only reducible ones are () A, Fe, Cl-, S2-, B, Cl-, CO, Na+, C, Fe2+, SO42-, NO3-, D, Fe3+, O2,, H2S (two) the law of the strong generation of the weak Rule: oxidant + reductant = reducing product + oxidation product (strongly oxidizing) (strongly reductive) (less reductive) (less oxidizing) Oxidation: oxidant reduction of oxidation product: reducing agent reducing product Application 1: we can judge the strength and reducibility of matter according to equation [example 3] according to the following reactions, it is estimated that the order of the reducibility of the substances concerned is from strong to weak H2SO3+I2+H2O=2HI+ H2SO4 2FeCl3+2HI=2FeCl2+2HCl+I2 3FeCl2+4HNO3=2FeCl3+NO = +2H2O+Fe (NO3) 3 A H2SO3,