Oxidation-reduction reactions of iron

Reflect and Apply Why do the electron-transfer reactions of the cytochromes differ in standard reduction potential, even though all the reactions involve the same oxidation-reduction reaction of iron ... 

Oxidation-reduction reactions of iron and manganese are also involved in nutrient release in flooded soil and sediments. Fe(III) and Mn(IV) serve as electron acceptors for organic matter decomposition or turnover. Organic nitrogen mineralization results in the release of nutrients such as ammonium nitrogen. Iron reduction is also coupled to phosphorous release in soils dominated by iron redox couples. 

How can oxidation-reduction reactions of iron and manganese influence nutrient release in flooded soil and sediment Under what conditions is phosphorous available ... 

Equation 2.41 is the dominant redox process in presence of overwhelming concentration of water as the solvent. As hydrogen ions are utilized in Equation 2.42, the pH would increase at corrosion locations, resulting in a simultaneous decline in the solution ORP. The Nemst relation can be applied to the oxidation-reduction reaction of iron as follows ... 

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