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    (Original post by MiracleLeaf)
    This is in the wrong thread I know, but you're all smart people, so could someone help with this A2 chemistry question? Outline how you carry out a simple laboratory process to show that the recrystallised product is a pure sample of N-phenylethanamide
    you just have to recall recrystallisation process. E.g. Dissolve the product in a minimum amount of hot solvent to ensure the solution that is saturated. Then filter the solution through a hot funnel to remove insoluble impurities and etc.
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    (Original post by Earth1)
    you just have to recall recrystallisation process. E.g. Dissolve the product in a minimum amount of hot solvent to ensure the solution that is saturated. Then filter the solution through a hot funnel to remove insoluble impurities and etc.
    Thank you!!
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    (Original post by MiracleLeaf)
    This is in the wrong thread I know, but you're all smart people, so could someone help with this A2 chemistry question? Outline how you carry out a simple laboratory process to show that the recrystallised product is a pure sample of N-phenylethanamide
    Is that not measure it's melting point? Go onto Chemrevise.org and go to the organic synthesis part for AQA and I think it outlines how you measure MP. You also have to say that it is sharp MP and doesn't have a range and compare the sharp MP to the real MP in data books for that compound and if it's the exact same then it's pure.


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    (Original post by michaela__)
    Is that not measure it's melting point? Go onto Chemrevise.org and go to the organic synthesis part for AQA and I think it outlines how you measure MP. You also have to say that it is sharp MP and doesn't have a range and compare the sharp MP to the real MP in data books for that compound and if it's the exact same then it's pure.


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    omg, you are absolutely right! Sorry, I didn't read the question carefully.
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    (Original post by MiracleLeaf)
    This is in the wrong thread I know, but you're all smart people, so could someone help with this A2 chemistry question? Outline how you carry out a simple laboratory process to show that the recrystallised product is a pure sample of N-phenylethanamide
    (Original post by michaela__)
    Is that not measure it's melting point? Go onto Chemrevise.org and go to the organic synthesis part for AQA and I think it outlines how you measure MP. You also have to say that it is sharp MP and doesn't have a range and compare the sharp MP to the real MP in data books for that compound and if it's the exact same then it's pure.


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    Don't know if you got an answer yet or not but...

    I'm a Scottish candidate but the answer I would give to that (having done a test on it 2 weeks ago only) would be you could use Thin Layer Chromatography. If it was a pure sample then only one spot would appear on the chromatogram.
    Also, Determination of the melting point can give an indication of the purity of a compound, as the presence of impurities lowers the melting point and broadens its melting temperature range. Since impurities lower the melting point, the technique of mixed melting point determination
    can be used to confirm the identity of a solid.

    But your best bet is to use TLC.


    Hope that helps
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    (Original post by Jeff458(#18))
    Don't know if you got an answer yet or not but...

    I'm a Scottish candidate but the answer I would give to that (having done a test on it 2 weeks ago only) would be you could use Thin Layer Chromatography. If it was a pure sample then only one spot would appear on the chromatogram.
    Also, Determination of the melting point can give an indication of the purity of a compound, as the presence of impurities lowers the melting point and broadens its melting temperature range. Since impurities lower the melting point, the technique of mixed melting point determination
    can be used to confirm the identity of a solid.

    But your best bet is to use TLC.


    Hope that helps
    I've not Learnt about TLC not sure if it's on the AQA spec for me but sounds interesting and a lot better than the other method we did in class 😉


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    (Original post by michaela__)
    I've not Learnt about TLC not sure if it's on the AQA spec for me but sounds interesting and a lot better than the other method we did in class 😉


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    Ah right, I guess us Scots are just much more ahead than you guys
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    (Original post by Jeff458(#18))
    Ah right, I guess us Scots are just much more ahead than you guys
    Oh snap.

    Name:  ImageUploadedByStudent Room1477939438.743923.jpg
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    (Original post by Jeff458(#18))
    Ah right, I guess us Scots are just much more ahead than you guys
    Maybe 😝😉


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    (Original post by jeff458(#18))
    ah right, i guess us scots are just much more ahead than you guys
    ahhahahahahahhahahahahahaa
 
 
 
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