Oxidizing agent, defined

Define oxidation, reduction, oxidation number, oxidizing agent, and reducing agent. 

A redox reaction can also be defined as a reaction between an oxidizing agent and a reducing agent, as illustrated in Figure 10.2. 

Many metals are fairly easily oxidized. The atmosphere contains a powerful oxidizing agent oxygen. Because metals are constantly in contact with oxygen, they are vulnerable to corrosion. In fact, the term corrosion is sometimes defined as the oxidation of metals exposed to the environment. In North America, about 20% to 25% of iron and steel production is used to replace objects that have been damaged or destroyed by corrosion. However, not all corrosion is harmful. For example, the green layer formed by the corrosion of a copper roof is considered attractive by many people. 

Because chemists have defined oxidation in terms of electron transfer, it is quite unnecessary for redox reactions to have oxygen as the oxidizing agent. Study the next example of metallic zinc reacting with chlorine gas to form zinc chloride ... 

Oil-sealed pumps are already quite satisfactorily protected against corrosion due to the oil film which will be present on all the component surfaces. Corrosion is defined here as the electrochemical dissolution of metals, i.e. the release of electrons by the metal atom and their acceptance by the oxidation agent (corrosive gas). A metal atom which is susceptible to corrosion must therefore be exposed to an active atom of the oxidation agent. 

The terms normal and normality are defined and applied as they were for acid-base equivalents. Again, the unique property of normality is that, for any electron-transfer reaction, when the reducing agent has just exactly consumed the oxidizing agent,... 

Before we review the methods used to determine surface acidity, we wish to define the type of acidity that should be measured. An acid is an electron-pair acceptor. In our opinion, the term acid should be limited to this definition rather than broadening the term to include oxidizing agents as well. We agree with Flockhart and Pink (10) who suggest a clear distinction be made between Lewis acid-Lewis base reactions (which involve coordinate bond formation) and oxidation-reduction reactions (which involve complete transfer of one or more electrons). 

Equivalent masses are so defined because equal numbers of equivalents of two substances react exactly with each other. This is true for neutralization because one H+ neutralizes one OH-, and for oxidation-reduction reaction because the number of electrons lost by the reducing agent equals the number gained by the oxidation agent (electrons cannot be eliminated—by the law of conservation of matter). 

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