Oxidation-reduction reducing agents

Simultaneous occurrence of oxidation and reduction in a chemical reaction. Oxidizing agent reducing agent oxidation-reduction pair (couple). 

The process of extraction requires first smelting (to obtain the crude metal) and then refining. In smelting, iron ore (usually an oxide) is mixed with coke and limestone and heated, and hot air (often enriched with oxygen) is blown in from beneath (in a blast furnace). At the lower, hotter part of the furnace, carbon monoxide is produced and this is the essential reducing agent. The reduction reactions occurring may be represented for simplicity as ... 

KEY TERMS disproportionation oxidizing agent reduction peroxide oxidation state reducing agent oxidation... 

There is compelling evidence that reducing agent oxidation and metal ion reduction are, more often than not, interdependent reactions. Nonetheless, virtually all established mechanisms of the electroless deposition fail to take into account this reaction interdependence. An alternative explanation is that the potentials applied in the partial solution cell studies are different to those measured in the full electroless solution studies. Notwithstanding some differences in the actual potentials at the inner Helmholtz plane in the full solution relative to the partial solutions, it is hard to see how this could be a universal reason for the difference in rates of deposition measured in both types of solution. 

In the same way that acid-base reactions involve the transfer of protons between proton donors and proton acceptors, redox reactions involve the transfer of electrons between electron donors, called reducing agents or reductants, and electron acceptors, called oxidizing agents or oxidants. Thus when a redox reaction takes place, a reductant loses electrons and is oxidized to its conjugate oxidaut ... 

Sodium hydride is used as a reducing agent and reduction catalyst. It also reduces oxide scale on metals. 

Production. Silicon is typically produced in a three-electrode, a-c submerged electric arc furnace by the carbothermic reduction of silicon dioxide (quartz) with carbonaceous reducing agents. The reductants consist of a mixture of coal (qv), charcoal, petroleum coke, and wood chips. Petroleum coke, if used, accounts for less than 10% of the total carbon requirements. Low ash bituminous coal, having a fixed carbon content of 55—70% and ash content of <4%, provides a majority of the required carbon. Typical carbon contribution is 65%. Charcoal, as a reductant, is highly reactive and varies in fixed carbon from 70—92%. Wood chips are added to the reductant mix to increase the raw material mix porosity, which improves the SiO (g) to solid carbon reaction. Silica is added to the furnace in the form of quartz, quartzite, or gravel. The key quartz requirements are friability and thermal stability. Depending on the desired silicon quality, the total oxide impurities in quartz may vary from 0.5—1%. 

Oxidizing agents are reduced in oxidation-reduction reactions. 

Redox reactions involve oxidation and reduction they occur by the exchange of electrons between reacting chemical species. Electrons (or electron density) are lost (or donated) in oxidation and gained (or accepted) in reduction. An oxidizing agent (or oxidant), which accepts electrons (and is thereby reduced), causes oxidation of a species. Similarly, reduction results from reaction with a reducing agent (or reductant), which donates electrons (and is oxidized). 

Reducing agents cause reduction to happen and are themselves oxidized. The iron(II) ion caused the reduction of the permanganate ion and was the reducing agent. Common ones are metals, hydrogen, and carbon. 

Various natural and synthetic organic compounds can act as reducing agents in reductive dissolution (Table 7-2). These compounds, when adsorbed to a mineral surface, can undergo oxidation and transfer electrons to surface... 

Oxidation and reduction steps complement one another, e.g. in reaction 7.1, magnesium is oxidized, while oxygen is reduced. Magnesium acts as the reducing agent or reductant, while O2 acts as the oxidizing agent or oxidant. 

Oxidizing Agent or Oxidant Reducing Agent or Reductant F°(V)... 

USE At low temps where reducing properties of sodium are undesirable as in the condensation of ketones and aide hydes with acid esters in soln wjth molten sodium hydroxide for the reduction of oxide scale on metals at high temps as a reducing agent and reduction catalyst. 

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