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    (Original post by haj101)
    ermmm.. I get N-methylethylphenylamine?? probs wrong :/
    But why N- , I was thinking also tho like methylethylphenylamine but then I thought like they're connected to N atom and not to the benzene ring so I got confused!

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    (Original post by PlayerBB)
    But why N- , I was thinking also tho like methylethylphenylamine but then I thought like they're connected to N atom and not to the benzene ring so I got confused!

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    Aaah true... im SO sorry i got confused with naming N-substituted amides (when we use N-). I think you are right
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    (Original post by haj101)
    Aaah true... im SO sorry i got confused with naming N-substituted amides (when we use N-). I think you are right
    It's okay and I think you use the N only when acyl chloride react with amines then it will form N-substituted amides

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    (Original post by PlayerBB)
    What do you mean by the amount of water like the volume or the number of moles of water that can be removed ? If the number of moles, then it is 0.1 moles, because 5.55g of anhydrous CaCl2 is used, it Mr is 111, the number of moles of CaCl2 is 0.05, the moles ratio of the CaCl2 to water is 1:2 so the number of moles of water used 0.1 which is the number of moles that will be removed from the organic liquid
    5.55/111 = 0.5 x 2

    gives you = 0.1 mol as the ratio is 1:2

    then if you want to find the mass you times the mol by the mr 18x 0.1 and get 1.8g
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    Does anyone have a revision tip or method that works for them for memorising reactions?
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    (Original post by ♥Samantha♥)
    Does anyone have a revision tip or method that works for them for memorising reactions?
    Yes the main way is repetition trust me thats how i learnt .... Like for example the reactions for the metal aqua ions write down all the equations and do this once every day. Once your confident try past paper Qs
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    (Original post by haj101)
    Hi- I've tried to give it a shot, forgive me if there are any mistakes...

    Okay so first I calculated the moles of NaOH: which is conc x (vol/1000) to get me 2.496 x 10-3 moles
    We know its a 1:2 ratio, for every one mole of acid, two moles of NaOH is reacted, so we divide the moles of NaOH we have calculated by 2, to get 1.248 x 10-3 moles of the acid (in 25cm3)
    Now we have the moles of the acid in 25cm3 we need to calculate moles in 250cm3 so we multiply the moles by 10 to get 0.01248 moles of the acid
    Now we have the moles of the acid in 250cm3. We can now divide the mass of the acid crystals by the moles to give us the Mr which is 1.575/0.01248= 126

    Now we have the Mr of H2C2O4.nH2O we then first find out the Mr of the first part: H2C2O4= which is 90. 126 - 90 is 36 so H20 is 36. The Mr of H20 is 18, so we divide 36/18 to get us n which is 2.
    So n is 2. I think.

    Hi, thank you very much that's the right answer I think I understand it now
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    (Original post by haj101)
    For this question, we first find out the moles of NaOH which is: (46.5/1000) x 0.095= to give us 4.4175 x 10^-3. REMEMBER THIS IS IN 25 CM3. You HAVE to multiply the moles by 10 (which i think you forgot to do) to get 0.044175 moles of acid.
    I assumed it's a 1:1 ratio so I then, divided the mass of the acid by the moles, so 3.88/0.044175= 87.8

    Just remember to not forget the volumes of the solutions- we may have to convert the moles in 25cm3 to 250cm3 which is why we had to multiply by 10
    Thank you for this as well
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    Hi everyone, I have a question: do we have to learn about the synthesis of 2-hydroxypropanoic acid (lactic acid) in the AQA A2 syllabus in the isomerism section? because its in my textbook and a revision guide but its not written on the actual spec..?

    Thank you,
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    Is anyone here doing Edexcel, if so,
    does anyone have the pdf of this book,


    or only the practical bits.
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    (Original post by Adorable98)
    Is anyone here doing Edexcel, if so,
    does anyone have the pdf of this book,


    or only the practical bits.
    Hey, I am doing Edexcel, I am using the black Hodder book, it has a chapter about organic synthesis, I have the cgp book and it has some good stuff about the practicals



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    (Original post by ilikechemistry)
    Thank you for this as well
    No problem
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    (Original post by ilikechemistry)
    Hi everyone, I have a question: do we have to learn about the synthesis of 2-hydroxypropanoic acid (lactic acid) in the AQA A2 syllabus in the isomerism section? because its in my textbook and a revision guide but its not written on the actual spec..?

    Thank you,
    Not everything is included in the spec you need to know the organic synthesis routes, (which may well include hydroxypropanoic acid)
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    (Original post by PlayerBB)
    Hey, I am doing Edexcel, I am using the black Hodder book, it has a chapter about organic synthesis, I have the cgp book and it has some good stuff about the practicals



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    I also have the CGP but the book that I'm looking for is the teacher's book and it has practicals stuff.
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    (Original post by Adorable98)
    I also have the CGP but the book that I'm looking for is the teacher's book and it has practicals stuff.
    I think it's called the Teacher's book so that teachers only can have it haha
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    (Original post by PlayerBB)
    I think it's called the Teacher's book so that teachers only can have it haha
    Yeah I know but I'm a home student .. that's why!
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    (Original post by Adorable98)
    Yeah I know but I'm a home student .. that's why!
    I am a kind of a home student as well, (studying some of the subjects by myself) as the school couldn't provide a teacher but I feel there will be no need for this book because if there was important practical details that are included in the exams and not included in the other books then they wouldn't just give it to teachers........But I am not saying you shouldn't get it, if you're convinced that it will benefit you then yeah go for it
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    can someone help mw with this question

    a compound contains C 62.08%, H 10.34% and O 27.58% by mass. find its emperical formula given that its relative molecular mass is 58
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    can someone explain nmr to me please http://www.thestudentroom.co.uk/show...9#post63764789
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    (Original post by itsastudentyo)
    can someone help mw with this question

    a compound contains C 62.08%, H 10.34% and O 27.58% by mass. find its emperical formula given that its relative molecular mass is 58
    First divide each element by its relative mass. Find the ratio of elements in the compound and calculate the Mr

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