Redox oxidizing agents

Redox Oxidizing Agent Reducing Agent Substance Oxidized Substance Reduced... 

Unlike the reactions that we have already considered, the equilibrium position of a redox reaction is rarely expressed by an equilibrium constant. Since redox reactions involve the transfer of electrons from a reducing agent to an oxidizing agent, it is convenient to consider the thermodynamics of the reaction in terms of the electron. 

Oxidation Reactions. Potassium permanganate is a versatile oxidizing agent characterized by a high standard electrode potential that can be used under a wide range of reaction conditions (100,133—141). The permanganate ion can participate in a reaction in any of three distinct redox couples. 

The Lo-Cat process, Hcensed by US Filter Company, and Dow/Shell s SulFerox process are additional Hquid redox processes. These processes have replaced the vanadium oxidizing agents used in the Stretford process with iron. Organic chelating compounds are used to provide water-soluble organometaHic complexes in the solution. As in the case of Stretford units, the solution is regenerated by contact with air. 

Polymerization Initiator. Some unsaturated monomers can be polymerized through the aid of free radicals generated, as transient intermediates, in the course of a redox reaction. The electron-transfer step during the redox process causes the scission of an intermediate to produce an active free radical. The ceric ion, Ce" ", is a strong one-electron oxidizing agent that can readily initiate the redox polymerization of, for example, vinyl monomers in aqueous media at near ambient temperatures (40). The reaction scheme is... 

Redox reactions are particularly instructive. If all thermodynamically allowed reactions in liquid NH3 were kinetically rapid, then no oxidizing agent more powerful than N2 and no reducing agent more powerful than H2 could exist in this solvent. Using data for solutions at 25° ... 

Low-spin, octahedral complexes are formed by ligands such as bipy, phen and CN , and their stability is presumably enhanced by the symmetrical configuration. [Fe(bipy)3] + and [Fe(phen)3] + are stable, intensely red complexes, the latter being employed as the redox indicator, ferroin , due to the sharp colour change which occurs when strong oxidizing agents are added to it ... 

In aqueous solutions the persulphate ion is known as a strong oxidizing agent, either alone or with activators. Thus, it has been extensively used as the initiator of vinyl polymerization [43-47]. However, only later, Kulkarni et al. [48] reported the graft copolymerization of AN onto cellulose using the Na2S203/K2S20s redox system. 

Redox reactions occur in the reduction of ores (metal oxides) into pure metals and the corrosion (oxidation) of pure metals in the presence of oxygen and water. Rusting iron, 4Fe + 30, + 611,0 —> 4Fe(OH), is a good example of metal oxidation. Strong oxidizing agents can be used as antiseptics (hydrogen peroxide, Fd,0,) or bleaches (sodium hypochlorite, NaOCl). 

The redox properties of quinones are crucial to the functioning of living cells, where compounds called ubiquinones act as biochemical oxidizing agents to mediate the electron-transfer processes involved in energy production. Ubiquinones, also called coenzymes Q, are components of the cells of all aerobic organisms, from the simplest bacterium to humans. They are so named because of their ubiquitous occurrence in nature. 

Redox Status Oxidizing agents stimulate activity... 

The Tf- CF system is preferred over Fenton s reagent because Ti4 is a less powerful oxidizing agent than Fc5+ and the above mentioned pathway and other side reactions are therefore of less consequence.252 Much of the discussion on redox initiation in Section 3.3.2.6.1 is also relevant to hydrogen peroxide. 

The oxidizing agent in a redox reaction is the species that is reduced. 

K.20 Classify each of the following reactions as precipitation, acid-base neutralization, or redox. If a precipitation reaction, write a net ionic equation if a neutralization reaction, identify the acid and the base if a redox reaction, identify the oxidizing agent and the reducing agent. 

A common laboratory technique for determining the concentration of a solute is titration (Fig. L.2). Titrations are usually either acid-base titrations, in which an acid reacts with a base, or redox titrations, in which the reaction is between a reducing agent and an oxidizing agent. Titrations are widely used to monitor water purity and blood composition and for quality control in the food industry. 

Balance each of the following skeletal equations and classify the reaction as Bronstcd-I. owry acid-base, Ix wis acid-base, or redox. For both types of acid-base reactions, identify the acid and the base. For redox reactions, identify the reducing agent and the oxidizing agent. 

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