Gain and Loss of Oxygen含碳链的氨基酸
The earliest view of oxidation and reduction is that of adding oxygen to form an oxide (oxidation) or removing oxygen (reduction). They always occur together. For example, in the burning of hydrogen 最早的氧化还原观念认为，氧化是指加入氧形成氧化物，而还原是指去除氧。它们总是同时发生。例如，在氢气燃烧时
the hydrogen is oxidized and the oxygen is reduced. The combination of nitrogen and oxygen which occurs at high temperatures follows the same pattern. 氢被氧化，氧被还原。在高温下发生的氮和氧的结合遵循相同的规律。
This formation of nitric oxide oxidizes the nitrogen and reduces the oxygen. In some reactions, the oxidation is most prominent. For example in the burning of methane, 这种硝酸盐的形成会氧化氮并还原氧。在某些反应中，氧化作用尤为显著。例如，在甲烷燃烧时，
both carbon and hydrogen are oxidized (gain oxygen). The accompanying reduction of oxygen is perhaps easier to see when you describe reduction as the gaining of hydrogen. 碳和氢都被氧化（获得氧）。当将还原定义为获得氢时，氧的还原可能更容易看出。
On the other hand, the reaction of lead dioxide at high temperatures appears to be just reduction. 另一方面，铅氧化物在高温下的反应似乎只是还原。
The reduction of the lead dioxide is clear, but the associated oxidation of oxygen is easier to see when you describe oxidation as the losing of electrons. 铅氧化物的还原是显而易见的，但当你将氧化定义为失去电子时，氧的氧化作用更容易被观察到。
2H₂ + O₂ → 2H₂O；N₂ + O₂ → 2NO；CH₄ + 2O₂ → CO₂ + 2H₂O；2PbO₂ → 2PbO + O₂ |
Index Oxidation/ Reduction concepts Reference Hill & Kolb Ch 8 索引 氧化还原概念 参考 Hill & Kolb 第8章 | ||
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Gain and Loss of Hydrogen氢的增减
The original view of oxidation and reduction is that of adding or removing oxygen . An alternative approach is to describe oxidation as the loss of hydrogen and reduction as the gaining of hydrogen. This has an advantage in describing the burning of methane. 关于氧化和还原的原始观点是添加或去除氧。另一种方法是将氧化描述为失去氢，还原描述为获得氢。这种方法在解释甲烷燃烧时具有优势。
With this approach it is clear that the carbon is oxidized (loses all four hydrogens) and that part of the oxygen is reduced (gains hydrogen). Another reaction where the hydrogen approach makes things clearer is the passing of methanol over a hot copper gauze to form formaldehyde and hydrogen gas (Hill and Kolb): 采用这种方法可以清楚地看出，碳被氧化（失去所有四个氢原子），而部分氧被还原（获得氢原子）。另一种使用氢原子方法使情况更清晰的反应是，将甲醇在热铜网上通过形成甲醛和氢气（Hill 和 Kolb）：
Both carbon-containing molecules have the same oxygen content, but the formation of the formaldehyde is seen to be oxidation because hydrogens are lost. The formation of H2 is a reduction process as the two released hydrogens get together. 含有碳的分子具有相同的氧含量，但甲醛的形成被观察到是氧化过程，因为氢原子被失去。氢气的形成是还原过程，因为释放出的两个氢原子结合在一起。
The formation of methanol from reacting carbon monoxide with hydrogen combines oxidation and reduction in the single molecular product. 一氧化碳与氢气反应生成甲醇的过程，同时发生了氧化和还原反应。
The CO is reduced because it gains hydrogen, and the hydrogen is oxidized by its association with the oxygen. CO被还原是因为它获得了氢，而氢则因与氧结合而被氧化。
CH₄ + 2O₂ → CO₂ + 2H₂O；CH₃OH → CH₂O + H₂CO + H₂ → CH₃OH |
Index Oxidation/ Reduction concepts Reference Hill & Kolb Ch 8 索引 氧化还原概念 参考 Hill & Kolb 第8章 | ||
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Gain and Loss of Electrons电子的获得与损失
The original view of oxidation and reduction is that of adding or removing oxygen. An alternative view is to describe oxidation as the losing of electrons and reduction as the gaining of electrons. One example in which this approach is of value is in the high temperature reaction of lead dioxide . 关于氧化和还原的原始观点是添加或去除氧。另一种观点是将氧化定义为失去电子，还原定义为获得电子。这种观点在铅 dioxide 高温反应中具有重要意义。
In this reaction the lead atoms gain an electron (reduction) while the oxygen loses electrons (oxidation). 在这个反应中，铅原子获得电子（还原），而氧原子失去电子（氧化）。
This electron view of oxidation and reduction helps you deal with the fact that "oxidation" can occur even when there is no oxygen! The definition of redox reactions is extended to include other reactions with nonmetals such as chlorine and bromine. For example, the reaction 这种电子观点有助于理解“氧化”可以在没有氧气的情况下发生这一事实。氧化还原反应的定义被扩展以包括诸如氯和溴等非金属参与的反应。例如，反应
Magnesium loses electrons and is therefore said to be "oxidized", whereas the chlorines gain electrons and are said to be reduced. Another way to judge that the chlorine has been reduced is the fact that the charge on the atoms is made more negative, or reduced. Treating that charge as an "oxidation number" is another way to characterize oxidation and reduction. 镁失去电子，因此被称为“被氧化”，而氯原子则获得电子，被称为“被还原”。另一种判断氯被还原的方法是，原子的电荷变得更负，或者说被减少了。将这种电荷视为“氧化数”是另一种描述氧化和还原的方式。
The view of oxidation and reduction as the loss and gain of electrons, respectively, is particularly appropriate for discussing reactions in electrochemical cells. For example, in the zinc-copper cell, the oxidation and reduction half-reactions are 将氧化和还原视为电子的失去和获得，对于讨论电化学电池中的反应特别合适。例如，在锌-铜电池中，氧化和还原的半反应是
2PbO₂ → 2PbO + O₂ Mg + Cl₂ → Mg²+ + 2Cl⁻ |
Index Oxidation/ Reduction concepts Reference Hill & Kolb Ch 8 索引 氧化还原概念 参考 Hill & Kolb 第8章 | ||||||
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Oxidation Number氧化数
The original view of oxidation and reduction is that of adding or removing oxygen. An alternative view which is useful in dealing with ions is to define an oxidation number which is equal to the net charge of the product of a reaction. Oxidation is then viewed as a reaction which increases the oxidation number and reduction as one which reduces the oxidation number. This view of oxidation and reduction helps you deal with the fact that "oxidation" can occur even when there is no oxygen! The definition of redox reactions is extended to include other reactions with nonmetals such as chlorine and bromine. For example, in the reaction 关于氧化和还原的原始观点是添加或去除氧。在处理离子时，另一种更有用的观点是定义氧化数，它等于反应产物的净电荷。氧化则被视作使氧化数增加的反应，而还原则是使氧化数减少的反应。这种对氧化和还原的理解有助于解释“氧化”即使在没有氧的情况下也能发生这一事实。将氧化还原反应的定义扩展到包括氯、溴等非金属的其他反应。例如，在反应
the Mg is seen to increase in oxidation number from 0 to 2 (oxidation) while the chlorine atoms experience a decrease in oxidation number from 0 to -1 (reduction). 镁的氧化数从0增加到2（氧化），而氯原子的氧化数从0降低到-1（还原）。
This is essentially equivalent to viewing oxidation and reduction as losing or gaining electrons, but may be easier to remember. 这基本上等同于将氧化和还原视为失去或获得电子的过程，但可能更容易记忆。
Mg + Cl₂ → Mg²⁺ + 2Cl⁻ |
Index Oxidation/ Reduction concepts Reference Hill & Kolb Ch 8 索引 氧化还原概念 参考 Hill & Kolb 第8章 | ||
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