Oxidation-Reduction Reactions Between Nonmetals

AIMS To understand oxidation and reduction in terms of oxidation states. To iearn to identify oxidizing and reducing agents. 

We have seen that oxidation-reduction reactions are characterized by a transfer of electrons. In some cases, the transfer literally occurs to form ions, such as in the reaction 

We can use oxidation states to verify that electron transfer has occurred. 

Thus in this reaction, we represent the electron transfer as follows  

In other cases the electron transfer occurs in a different sense, such as in the combustion of methane (the oxidation state for each atom is given below each reactant and product). 

OBJECTIVES To understand oxidation and reduction in terms of oxidation states. 

Note that the oxidation state of oxygen in O2 is 0 because the oxygen is in elemental form. In this reaction there are no ionic compounds, but we can still describe the process in terms of the transfer of electrons. Note that carbon undergoes a change in oxidation state from -4 in CH4 to +4 in CO2. Such a change can be accounted for by a loss of eight electrons  

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So far we have emphasized electron transfer (oxidation-reduction) reactions that involve a metal and a nonmetal. Electron transfer reactions can also take place between two nonmetals. We will not discuss these reactions in detail here. All we will say at this point is that one sure sign of an oxidation-reduction reaction between nonmetals is the presence of oxygen, 0 g), as a reactant or product. In fact, oxidation got its name from oxygen. Thus the reactions... 

Oxidation States 1 7.3 Oxidation-Reduction Reactions Between Nonmetals... 

What is essential in an oxidation-reduction reaction What is oxidation What is reduction Can an oxidation reaction take place without a reduction reaction also taking place Why Write a balanced chemical equation illustrating an oxidation-reduction reaction between a metal and a nonmetal. Indicate which species is oxidized and which is reduced. 

This is an oxidation-reduction reaction in which chlorine oxidizes sodium to form Na+ and Cl- ions. In the reactions between metals and nonmetals it is typical for the nonmetal to behave as the oxidizing agent and the metal to behave as the reducing agent, as shown by the following reactions ... 

In combination reactions, two substances, either elements or compounds, react to produce a single compotmd. One type of combination reaction involves two elements. Most metals react with most nonmetals to form ionic compounds. The products can be predicted from the charges expected for cations of the metal and anions of the nonmetal. For example, the product of the reaction between aluminum and bromine can be predicted from the following charges 3-1- for aluminum ion and 1— for bromide ion. Since there is a change in the oxidation numbers of the elements, this type of reaction is an oxidation-reduction reaction ... 

Reactions between metals and nonmetals involve a transfer of electrons from the metal to the nonmetal which is called an oxidation-reduction reaction. 

Reactions Between Nonmetals Although we can identify reactions between metals and nonmetals as redox reactions, it is more difficult to decide whether a given reaction between nonmetals is a redox reaction. In fact, many of fhe mosf significanf redox reactions involve only nonmetals. For example, combustion reactions such as methane burning in oxygen are oxidation-reduction reactions. 

I really like to call my interest the study of oxidation-reduction (redox) reactions, and insofar as such reactions between metal ions are concerned, there was little prior work when I began my own. Werner had encountered redox reactions in the coirrse of his research and, in fact, made good use of them in the preparative procedures he developed. I m not sure that he thought much about the fundamental difference between them and the reactions he was primarily interested in, which were substitution reactions of metal complexes (coordination complexes). Many of the basic ideas underlying redox reactions were developed in the study of nonmetal chemistry. For example, my mentor at Berkeley became an expert in the redox chemistry of halogenates, after working with Professor Luther in Germany in the first part of this century. 

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