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What colour do you observe when Potassium manganate (VII) dissolve in acid and alkali Watch

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    So according to my booklet potassium mangante (VII) goes from purple to colourless both in acid and in alkali, but turns brown when it's neutral.



    Whereas on Chemguide, potassium mangante (VII) goes from purple to colourless in acid and
    goes from purple to brownin alkali.
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    Alkenes react with potassium manganate(VII) solution in the cold. The colour change depends on whether the potassium manganate(VII) is used under acidic or alkaline conditions.

    If the potassium manganate(VII) solution is acidified with dilute sulphuric acid, the purple solution becomes colourless.

    If the potassium manganate(VII) solution is made slightly alkaline (often by adding sodium carbonate solution), the purple solution first becomes dark green and then produces a dark brown precipitate.
    So which one is correct?
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    Sorry.
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    (Original post by Adorable98)
    So according to my booklet potassium mangante (VII) goes from purple to colourless both in acid and in alkali, but turns brown when it's neutral.



    Whereas on Chemguide, potassium mangante (VII) goes from purple to colourless in acid and
    goes from purple to brownin alkali.
    Spoiler:
    Show
    Alkenes react with potassium manganate(VII) solution in the cold. The colour change depends on whether the potassium manganate(VII) is used under acidic or alkaline conditions.

    If the potassium manganate(VII) solution is acidified with dilute sulphuric acid, the purple solution becomes colourless.

    If the potassium manganate(VII) solution is made slightly alkaline (often by adding sodium carbonate solution), the purple solution first becomes dark green and then produces a dark brown precipitate.
    So which one is correct?
    chemguide
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    http://www.thestudentroom.co.uk/show....php?t=1173227
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    The chemiguide is right, from what I know potassium manganate exist is both acidic and alkaline forms, and according to the chemiguide the colour changes are correct.

    If you are still in doubt I recommend you good or watch a youtube video.
 
 
 
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