Reaction Stoichiometry in Solutions Oxidation-Reduction Titrations

4 Reaction Stoichiometry in Solutions Oxidation—Reduction Titrations 

Magnesium is oxidized in this process it gives up electrons as its oxidation number increases from 0 (in elemental Mg) to -1-2 (in MgO). Oxygen, which accepts these electrons, is said to be reduced its oxidation number decreases from 0 to —2. The transfer of electrons (e ) can be indicated with arrows  

Originally, the term oxidation referred only to reactions with oxygen. It now is used to describe any process in which the oxidation number of a species increases, even if oxygen is not involved in the reaction. When calcium combines with chlorine to form calcium chloride. 

Oxidation-reduction reactions are among the most important in chemistry, biochemistry, and industry. Combustion of coal, natural gas, and gasoline for heat and power are redox reactions, as are the recovery of metals such as iron and aluminum from their oxide ores and the production of chemicals such as sulfuric acid from sulfur, air, and water. The human body metabolizes sugars through redox reactions to obtain energy the reaction products are liquid water and gaseous carbon dioxide. 

Determine whether the following equations represent oxidation-reduction reactions. 

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