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    For my AH chemistry investigation I am investigating the 3-step synthesis of paracetamol and I would like to be able to test the purity of the paracetamol I make but I am really struggling to find out how I would do this, does any one know? Any links to methods or just generally how to test its purity would be really helpful! Thanks!
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    Compare it with a samples of known purity (e.g. a paracetamol tablet dissolved in water and then using different dilutions to make a calibration curve) for a reaction it participates in using a titration?

    GC would work if that's available (it probably isn't).
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    (Original post by alow)
    Compare it with a samples of known purity (e.g. a paracetamol tablet dissolved in water and then using different dilutions to make a calibration curve) for a reaction it participates in using a titration?

    GC would work if that's available (it probably isn't).
    HPLC
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    Ordinarily, you'd get an HPLC trace and/or an NMR spectrum. You can't get a good measure for an organic compound likke that without some sort of spectroscopy or similar analytical technique.

    If you don't have access to these, you could possibly try and titrate it if you get yourself a strong enough base or acid. That seems like a lot of fuss for low accuracy, though.
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    (Original post by alow)
    Compare it with a samples of known purity (e.g. a paracetamol tablet dissolved in water and then using different dilutions to make a calibration curve) for a reaction it participates in using a titration?

    GC would work if that's available (it probably isn't).
    Thanks!
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    (Original post by FlowerFaerie087)
    Ordinarily, you'd get an HPLC trace and/or an NMR spectrum. You can't get a good measure for an organic compound likke that without some sort of spectroscopy or similar analytical technique.

    If you don't have access to these, you could possibly try and titrate it if you get yourself a strong enough base or acid. That seems like a lot of fuss for low accuracy, though.
    Yeah that makes a lot of sense but I think it is more likely my teacher will want me to titrate it...
    Thank you!
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    Haha! It's hard to imagine doing such a thing in a professional lab, but I'm confident you can make it work. It will probably be hard for you to get a sufficiently strong base, so I would titrate it with acid. Again, it'll need to be a strong acid though, so be careful

    You may have already done this, but if you have access to an organic solvent you could further purify your paracetamol by dissolving it in a suitable organic solvent, and adding strong acid. Crystals will precipitate out, and you can recrystallize them from water - google to find out how to do that. Recrystallization is a bit of an art, so now is a great time to do your first one. If you did this, you'd have to add base to get back to just paracetamol rather than its hydrochloride salt, but paracetamol HCl is also used therapeutically.
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    (Original post by FlowerFaerie087)
    Haha! It's hard to imagine doing such a thing in a professional lab, but I'm confident you can make it work. It will probably be hard for you to get a sufficiently strong base, so I would titrate it with acid. Again, it'll need to be a strong acid though, so be careful

    You may have already done this, but if you have access to an organic solvent you could further purify your paracetamol by dissolving it in a suitable organic solvent, and adding strong acid. Crystals will precipitate out, and you can recrystallize them from water - google to find out how to do that. Recrystallization is a bit of an art, so now is a great time to do your first one. If you did this, you'd have to add base to get back to just paracetamol rather than its hydrochloride salt, but paracetamol HCl is also used therapeutically.
    Thanks so much! I am planning on recrystallising it
 
 
 
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