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    how many carbon environments in 1,2-dimethylbenzene, 1,3-dimethylbenzene and ethylbenzene??? thanks
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    (Original post by otrivine)
    quick question

    http://www.ocr.org.uk/Images/65129-q...d-analysis.pdf

    why is it only aspirin reacts with the Na2CO3 cause both compounds consist of carbonyl groups/?
    It's because the COOH reacts with it to make a salt, CO2 and H2O. Phenol is too weak of an acid to actually react with NaCO3. This is actually a test to tell them apart because the one with COOH will fizz
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    (Original post by wl1)
    Great, thanks. So -NH and -OH protons will have singlet splitting patterns even if they are adjacent to a carbon with a proton?

    Yes unless if they state in the question using d20 by proton exchange these peaks will no give of a peak once d20 is added
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    (Original post by Strawberry x3)
    It's because the COOH reacts with it to make a salt, CO2 and H2O. Phenol is too weak of an acid to actually react with NaCO3. This is actually a test to tell them apart because the one with COOH will fizz
    I see if they ask us why this can react with Na2co3 and that cant, what should we say?
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    (Original post by Meado123)
    Hey can someone please help me out on Q3 C on the June 2010 paper?

    Paper: http://www.ocr.org.uk/Images/59707-q...d-analysis.pdf

    Mark scheme: http://www.ocr.org.uk/Images/59704-m...lysis-june.pdf
    This question doesn't give information on the whole spectrum but since they said there is doublet at chemical shift 0.9 of area 6, the aldehyde has two methyl groups bonded to CH the only aldehyde with the given molecular formula and that sequence is(CH3)2CHCH2CHO

    hope that helps
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    (Original post by AFC_123456789)
    how many carbon environments in 1,2-dimethylbenzene, 1,3-dimethylbenzene and ethylbenzene??? thanks
    4/4/6 I think
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    (Original post by clard254)
    This question doesn't give information on the whole spectrum but since they said there is doublet at chemical shift 0.9 of area 6, the aldehyde has two methyl groups bonded to CH the only aldehyde with the given molecular formula and that sequence is(CH3)2CHCH2CHO

    hope that helps
    Thankyou, yes i understand now
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    Just say that COOH is strong enough to react with NaCO3 while phenol isn't I think.
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    can someone please tell me all the reagents and conditions we are expected to know for the exam?
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    (Original post by mrmccarl)
    can someone please tell me all the reagents and conditions we are expected to know for the exam?
    Its been posted, check the previous recent post for a massive list.

    They are in the textbook too summarised if you looked at the synthesis topic.

    Posted from TSR Mobile
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    (CH3CO)2O + C6H5OH is a nice ester formation question
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    (Original post by AFC_123456789)
    how many carbon environments in 1,2-dimethylbenzene, 1,3-dimethylbenzene and ethylbenzene??? thanks
    I make it 4, 5, 6
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    (Original post by Raj Kang)
    2,4 dinitophenylhydrazine + methanol + sulpuhric acid = bradys
    i think 2,4-dnp is ok
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    (Original post by otrivine)
    quick question

    http://www.ocr.org.uk/Images/65129-q...d-analysis.pdf

    why is it only aspirin reacts with the Na2CO3 cause both compounds consist of carbonyl groups/?
    its not about the carbonyl C=O, that part does not react with the carbonate.

    rememeber that it is acid +carbonate that reacts to from salt and water

    in reactions of phenols, phenol is a very weak acid , phenol cannot react with carbonates.


    remember that :

    phenol +carbonate --->no reaction

    phenol + metal e.g. Na --> reaction

    edit :i think that right, correct me if im wrong
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    http://www.ocr.org.uk/Images/59704-m...lysis-june.pdf

    question 2)c)i

    why do they not put on both sides O-Na+

    is because it can form no charge overall?
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    (Original post by Zzzyax)
    its not about the carbonyl C=O, that part does not react with the carbonate.

    rememeber that it is acid +carbonate that reacts to from salt and water

    in reactions of phenols, phenol is a very weak acid , phenol cannot react with carbonates.


    remember that :

    phenol +carbonate --->no reaction

    phenol + metal e.g. Na --> reaction

    thank you

    but please describe why
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    5 days revision,need a B atleast
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    (Original post by otrivine)
    thank you

    but please describe why
    like i said phenol is such a weak acid it cannot react with carbonates, just remember that.
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    (Original post by D4rth)
    Its been posted, check the previous recent post for a massive list.

    They are in the textbook too summarised if you looked at the synthesis topic.

    Posted from TSR Mobile
    cheers.
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    anyone else feeling depressed after that C4 maths exam?
 
 
 
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