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    I need to work out what an unkonwn solution is , with different tests one of them was with potassium manganate(vii) , it turned brown, so I thought it was an alkene but it also reacted with sodium hydrogen carbonate but I don't know if alkenes do or not:confused:
    Can someone help please??
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    I certainly don't know of alkene reacting with that. The usual test for an alkene is bromine water.

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    (Original post by JMaydom)
    I certainly don't know of alkene reacting with that. The usual test for an alkene is bromine water.

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    Do you know what the solution is?
    Effervescence with Fehling's
    Turns brown with potassium manganate vii
    Effervescence with sodium hydrogen carbonate
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    (Original post by Mariah246)
    I need to work out what an unkonwn solution is , with different tests one of them was with potassium manganate(vii) , it turned brown, so I thought it was an alkene but it also reacted with sodium hydrogen carbonate but I don't know if alkenes do or not:confused:
    Can someone help please??
    Alkenes most certainly do not react with NaHCO3. Potassium Manganate(VII) is an oxidising agent so you need to consider what other compounds get oxidised (alcohols and aldehydes). Aldehydes also react with Fehling's. Your compound is probably an aldehyde.
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    (Original post by Mariah246)
    Do you know what the solution is?
    Effervescence with Fehling's
    Turns brown with potassium manganate vii
    Effervescence with sodium hydrogen carbonate

    (Original post by originaltitle)
    Alkenes most certainly do not react with NaHCO3. Potassium Manganate(VII) is an oxidising agent so you need to consider what other compounds get oxidised (alcohols and aldehydes). Aldehydes also react with Fehling's. Your compound is probably an aldehyde.
    Bubbling with sodium bicarbonate implies that your product is acidic enough to be deprotonated by it. However a simple carboxylic acids will not get oxidised, so my guess is that there are multiple functional groups present.
 
 
 
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