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    (Original post by itsConnor_)
    But surely if stationary phase is solid, it separates by adsorption and if the stationary phase is a liquid, it separates by relative solubilities?
    Yeah but it doesn't tell you the stationary phase, it asks about gas/liquid chromatography and gas separates by relative solubilities right?
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    How would you form a carboxylic acid from its salt?
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    Name:  ImageUploadedByStudent Room1465760964.338118.jpg
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Size:  122.2 KB guys how are we supposed to know where the double bond is in the structure?!i put it randomly anywhere but in the ms they wanted a specific structure


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    (Original post by Hunnybeebee)
    I'm having so many panic attacks about this exam i'm actually considering not going in to do the exam at all
    dont think like that! just know that each and every single one of us is feeling that way! dont stress, try your best and forget the rest! 😊


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    (Original post by ranz)
    Name:  ImageUploadedByStudent Room1465760964.338118.jpg
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Size:  122.2 KB guys how are we supposed to know where the double bond is in the structure?!i put it randomly anywhere but in the ms they wanted a specific structure


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    It says F is an amino acid, so consider the general formula of an amino acid: http://www.mrothery.co.uk/images/aa.GIF
    If E is oxidised to an amino acid by Tollens, that means an ALDEHYDE group is being oxidised to a CARBOXYLIC ACID group

    One carbon must be bonded to an NH2, a COOH, an H and a R group (for F) - hence the only thing you can change is the R group and the double bond must be in the R group. If there is no double bond, it wont fit the molecular formula it gives
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    (Original post by ranz)
    dont think like that! just know that each and every single one of us is feeling that way! dont stress, try your best and forget the rest! 😊


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    No I seriously I can't take it any more :'(
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    (Original post by AqsaMx)
    How would you form a carboxylic acid from its salt?
    How would you form a 'normal' acid from it's salt?

    (Can you even form an acid from it's salt....)
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    legit hate chemistry rn :[
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    (Original post by Serine Soul)
    How would you form a 'normal' acid from it's salt?

    (Can you even form an acid from it's salt....)
    I don't know if this is right but for example CH3COO-Na + HCl > CH3COOH + NaCl? Is this right?

    I think you can, my teacher gave it as a set of questions
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    (Original post by Hunnybeebee)
    No I seriously I can't take it any more :'(
    Hey! I'll not have that kind of talk!
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    (Original post by AqsaMx)
    I don't know if this is right but for example CH3COO-Na + HCl > CH3COOH + NaCl? Is this right?

    I think you can, my teacher gave it as a set of questions
    Ah yes of course!
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    what do you guys think is gonna come up for the NMR imagine if they ask us to draw one- bye
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    (Original post by Hunnybeebee)
    No I seriously I can't take it any more :'(
    You'll be okay, there's loads of people here who will help you with anything you're stuck on. I know I start feeling like that when I've been doing too much work, maybe you need to take a break and relax a bit, just completely forget about the exam for a couple of hours and do something you like. It always does me a world of good.

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    (Original post by itsConnor_)
    It says F is an amino acid, so consider the general formula of an amino acid: http://www.mrothery.co.uk/images/aa.GIF
    If E is oxidised to an amino acid by Tollens, that means an ALDEHYDE group is being oxidised to a CARBOXYLIC ACID group

    One carbon must be bonded to an NH2, a COOH, an H and a R group (for F) - hence the only thing you can change is the R group and the double bond must be in the R group. If there is no double bond, it wont fit the molecular formula it gives
    thank h soo much! tbh i didnt even think about it being an amino acid, i totally overlooked that and focused more on it being an optical isomer


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    Name:  ImageUploadedByStudent Room1465763175.471769.jpg
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    guys how would one identify the final strucutre out of four isomers? what info would u use to determine that


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    (Original post by AqsaMx)
    Attachment 548665

    Can anyone explain the relative heights question? What's it even asking?
    Which paper is this? I want to attempt it myself.
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    (Original post by ranz)
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    guys how would one identify the final strucutre out of four isomers? what info would u use to determine that


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    I can't see the whole question, but look at the number of peaks on the c13 spectrum and look at your isomers and cross out any that have more or less environments than the peak
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    How are you structuring your answers for the long answer NMR questions
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    (Original post by ranz)
    Name:  ImageUploadedByStudent Room1465763175.471769.jpg
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    guys how would one identify the final strucutre out of four isomers? what info would u use to determine that


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    Yeah it's the number of C-13 peaks = no. of carbon environments. Only one of the isomers has 5 carbon environments
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    (Original post by yoda123)
    How are you structuring your answers for the long answer NMR questions
    Table of peaks!
 
 
 
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