Reducing agents definition

Reducing agents present similar problems. They react with a broad spectrum of chemical classes, and the reactions can be exothermic and violent. Reducing agents are, by definition, highly oxidizable and may react with air or moisture in the air. Common reducing agents include ... 

In the actual oxidation-reduction process electrons are transferred from the reducing agent to the oxidising agent. This leads to the following definitions. 

Thus, a reducing agent donates electrons, while an oxidizing agent receives them. The Bronsted-Lowry definitions of acid and base specify that... 

In the most general sense, any anion radical produced by reduction with a metal, or by electrolytic reduction in the presence of a metallic counterion could be considered an organometallic anion radical. Any review based on such a definition would be monumental. To achieve a manageable volume of material, with a content suitable to the context of this series, we have limited this chapter to anion radicals produced from organometallic compounds. Anion radicals for which the metal is present solely as the reducing agent or counterion have, for the most part, been excluded. 

Volumetric Estimation.—Tellurium may be determined by oxidation from the tellurous to the telluric condition, using an excess of potassium dichromatc or permanganate and subsequently titrating the excess of oxidising agent with a standard solution of a suitable reducing agent.2 In order to obtain accurate results with the potassium dichromate titration, certain very definite steps in the procedure are essential, and it is necessary to control the course of the reaction, since hydrochloric and telluric acids interact with production of chlorine. 

In contrast to outer-sphere reactions, the simple observation that a reaction occurs by an inner-sphere mechanism necessarily introduces an element of structural definition. The relative dispositions of the oxidizing and reducing agents are immediately established and, except for structurally flexible bridging ligands such as NC5H4(CH2) C5H4N, the internuclear separation between redox sites can be inferred from known bond distances. Even so, bimolecular inner-sphere reactions necessarily occur by a sequence of elementary steps (Scheme 2) and the observed rate constant may include contributions from any of the series of steps. 

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