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Karlo Vizec

Potassium permanganate (VII) + glucose + sodium hydroxide =?

Chris Beulah  Follow

This is a redox reaction in which the permanganate ion is reduced and the glucose is oxidised. Potassium permanganate is usually used in acid solution and under these conditions is a very powerful oxidising agent in which the manganese is reduced from the oxidation state of +7 to +2 with a colour change from purple to colourless (actually extremely pale pink). In alkaline solution manganese is only reduced from +7 to +6 changing colour from purple to green. (The blue colour you mention is due to a mixture of purple and green). The green manganate(VI) ion is unstable and slowly disproportionates to manganate(VII) (purple) and manganese(IV) oxide which is brown. The manganate(VII) goes on to react as before until the brown manganese(IV) oxide is all that remains. In alkaline solution this tends to form a colloidal suspension which (if fairly dilute) can appear orange. The oxidation of the glucose forms no coloured productss.

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Eric Ondler  Follow
en.wikipedia.org/wiki/…More
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Jeffrey Werbock  Follow
Alternatively the blue colour might be Manganate(V) ( More
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Henry Boyter  Follow
), which disproportionates to Maganate(VI) and MnO2, and then as in the answerMore
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