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This experiment is traditionally carried out in two parts.

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A. The reaction of potassium permanganate with glycerol

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B. The reduction of iron(III) oxide with aluminium thermite reaction) to produce iron metal.

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Both lab partners should be involved in both parts so that you can observe what occurs and report your observations.

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In redox processes, one chemical acts as the oxidising agent and another as reducing agent. Some materials contain both functions in one compound. This is the basis of high explosive materials such as nitroglycerine and TNT; they need no external oxidising agents. A more benign example is ammonium dichromate, (NH4)2[Cr2O7], which reacts when ignited to produce a 'chemical volcano' shower of Cr2O3 along with N2 and H2O.

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Some chemical reactions generate so much heat (are exothermic) that they accelerate violently and can readily get out of control. Extreme care must be taken to isolate, contain and control such reactions. This experiment illustrates two such oxidation/reduction reactions that fall into this category: the oxidation of glycerol by potassium permanganate, and the thermite reaction reducing iron(III) oxide with aluminium.

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A balanced equation for the oxidation of glycerol by KMnO4 is given below. This is needed to answer questions coming up.

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14KMnO4 + 4C3H5(OH)3 $\\rightarrow$ 7Mn2O3 + 7K2CO3 + 5CO2 + 16H2O

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What is the oxidation number of manganese in KMnO4?

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Please enter only integer values and no sign.

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What is the oxidation number of manganese in Mn2O3?

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Please enter only integer values and no sign.

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