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Oxidisation of methanoic acid by kmno4

  1. Nov 30, 2018 #1
    i was reading through my alkene notes and it said for strong oxidation of alkenes in acidic conditions results in formation of ketone , carboxylic acid or carbondioxide and water. But my notes doesn't detail the mechanism so i found some videos explaining how ketones and carboxylic acid may be formed . and from what i understand if the oxidation process results in formation of methanoic acid , it is further oxidised into co2 and water. many website just state this . i am curious why it only happens to methanoic acid and not like ethanoic acid . Some websites said it is because of the hydrogen being the r group but if that is true then why is ethandioic acid also oxidised by kmno4 into co2 and water. I am really confused. it would be really helpful if someone could explain this or could link to a website with the mechanism(it helps me to understand better). I am sorry if i dont make sense.
     
    Last edited: Nov 30, 2018
  2. jcsd
  3. Nov 30, 2018 #2

    Borek

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    Staff: Mentor

    Methanoic acid is a bit similar in its properties to aldehydes (look at the molecule, can you see the -CHO group?)

    I believe oxalic acid is a very specific case, not necessarily following rules that hold for most organic compounds.
     
  4. Nov 30, 2018 #3
    thats the thing i haven't learnt about aldehydes yet many websites said the same thing but then why does it work for ethandioc acid it does not have coh group
     
  5. Nov 30, 2018 #4

    Borek

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    Staff: Mentor

    You do understand that oxalic acid and ethanedioic acid are the same substance and I already addressed your question?
     
  6. Nov 30, 2018 #5
    ya i do but i dont quite get what you mean by that statement as in why that exception for oxalic acid


    edit :
    is there anywhere i can look up for the mechanism of this oxidisation
     
  7. Dec 3, 2018 #6

    DrDu

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    Science Advisor

    It certainly is possible to decompose oxalic acid into CO and CO2. That's a classic method to produce CO in the laboratory. It is also possible to oxidize oxalic acid to CO2. That is basically the mechanism behind chemiluminescent lightsticks.
     
  8. Dec 4, 2018 at 6:00 AM #7
    Somewhat specific but I wouldn't say "very specific".
    Under the oxidation conditions like KMnO4, most C-C bonds are not oxidized. So CH3COOH is not oxidized. However, some C-C bonds are weakened - HOOC-COOH among them, but I remember there are others. Don't quite remember which others, though.
     
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