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    (Original post by tkoki1993)
    Just came across something on the spec I have NO idea about

    Its the uses of ionic liquids. Can someone please explain it to me please. Its come up in an exam before but you just had to define what an ionic liquid is.

    thanks
    Ionic liquids are used to carry out Friedel-Crafts acylation reactions - they are liquids at room temperature even though they contain ions. They are green alternatives to ordinary solvents because:

    .Their low volatility reduces emissions
    .Their low volatility and low toxicity increases safety
    .Friedel-Crafts reactions can be carried out at lower temperatures so energy costs are lower
    .The ionic liquid can easily be recycled, saving resources and money
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    (Original post by jpurkis1)
    According to Wikipedia;

    'An ionic liquid is a salt in the liquid state'.

    Which past paper was it in?
    its in the specimen paper
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    (Original post by WalterWhite)
    Ionic liquids are used to carry out Friedel-Crafts acylation reactions - they are liquids at room temperature even though they contain ions. They are green alternatives to ordinary solvents because:

    .Their low volatility reduces emissions
    .Their low volatility and low toxicity increases safety
    .Friedel-Crafts reactions can be carried out at lower temperatures so energy costs are lower
    .The ionic liquid can easily be recycled, saving resources and money
    thanks
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    any tips of what you guys think is coming up? anyone know what came up in January?
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    (Original post by kinkin)
    any tips of what you guys think is coming up? anyone know what came up in January?
    Our teacher has said repeatedly that GLC is going to make an appearance, given it's absence from the Jun 2010 and Jan 2011 papers...
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    yes ive got a feeling that GLC is gona *** up!

    I cant stand revising the tool kit- reagants and conditions!

    and NMR is in almost every paper majority of the time! It will probably tell us to identify a compound, or compare it with mass spec/infrared....
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    (Original post by jpurkis1)
    Our teacher has said repeatedly that GLC is going to make an appearance, given it's absence from the Jun 2010 and Jan 2011 papers...
    thanks GLC=Gas liquid chromatography lol not sure. Anything else you think is going to come up?
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    can anyone help me out, been reading books but cant see a good explanation of N.M.R i understand the jist of it but what does it mean when a spectrum has more than one peak, does it have anything to do with n+1 rule, if anyone could help me out with N.M.R would be much appreciated
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    (Original post by kinkin)
    can anyone help me out, been reading books but cant see a good explanation of N.M.R i understand the jist of it but what does it mean when a spectrum has more than one peak, does it have anything to do with n+1 rule, if anyone could help me out with N.M.R would be much appreciated
    Search NMR Chemguide on google
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    (Original post by gozatron)
    Search NMR Chemguide on google
    thanks for our syllabus do we only consider high resolution NMR or do we need to know about both high and low?
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    Goodluck!!!!
    gonna have an early night
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    (Original post by kinkin)
    thanks for our syllabus do we only consider high resolution NMR or do we need to know about both high and low?
    Both I think.
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    (Original post by kinkin)
    can anyone help me out, been reading books but cant see a good explanation of N.M.R i understand the jist of it but what does it mean when a spectrum has more than one peak, does it have anything to do with n+1 rule, if anyone could help me out with N.M.R would be much appreciated
    DifferENt peaks in the spectrum represent different environments for the H+/protons; low and high-resolution n.m.r.;
    For example, CH3CH2OH, or ethanol, would have 3 peaks because there are 3 different environments for the protons.
    CH3,
    CH2,
    OH

    The 'n+1' rule only applies if the question asks for reference to the splitting pattern or shows a high-resolution spectrum.
    It refers to the number of adjacent protons. Adjacent protons generate their own localised magnetic field and therefore alter the resonance of the measured protons.
    'n+1' refers to the following pattern, when the measured proton is adjacent to:
    -RC(R)R - No protons - singlet(1)
    -RC(H)R - 1 proton - doublet (2)
    -HC(H)R - 2 protons - triplet (3)
    -HC(H)H - 3 protons - quartet (4)

    The splitting pattern of a high-resolution n.m.r peak is +1 of the number of adjacent protons (n). Therefore 'n+1'.
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    (Original post by jpurkis1)
    DifferENt peaks in the spectrum represent different environments for the H+/protons; low and high-resolution n.m.r.;
    For example, CH3CH2OH, or ethanol, would have 3 peaks because there are 3 different environments for the protons.
    CH3,
    CH2,
    OH

    The 'n+1' rule only applies if the question asks for reference to the splitting pattern or shows a high-resolution spectrum.
    It refers to the number of adjacent protons. Adjacent protons generate their own localised magnetic field and therefore alter the resonance of the measured protons.
    'n+1' refers to the following pattern, when the measured proton is adjacent to:
    -RC(R)R - No protons - singlet(1)
    -RC(H)R - 1 proton - doublet (2)
    -HC(H)R - 2 protons - triplet (3)
    -HC(H)H - 3 protons - quartet (4)

    The splitting pattern of a high-resolution n.m.r peak is +1 of the number of adjacent protons (n). Therefore 'n+1'.
    thanks alot really cleared up the n+1 rules for me thanks. Does anyone have any tips of staying calm in an exam in F334 my mind went completely blank and lost mark on things I kinda knew, if anyone had any tips will be very much appreciated.
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    Was it just me or did you get a messed up answer for the NMR question, the values on table gave me some messed up compounds, overall paper was okay, not as hard any january, what did you lot think of it.
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    (Original post by kinkin)
    Was it just me or did you get a messed up answer for the NMR question, the values on table gave me some messed up compounds, overall paper was okay, not as hard any january, what did you lot think of it.
    I don't think that the NMR question wanted a the ppm chemical shifts of the compounds; it asked for the compound identification based on the peaks, their areas and the splitting patterns (something aimed at targetting the higher grade candidates ).

    Overall, I thought the paper was alright; lots on synoptic stuff (electronegativity, dipoles and bond polarities...), but there was stuff on reaction mechanisms which was alright. I didn't like the 4-mark maths question at the end though...:mad:
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    (Original post by jpurkis1)
    I don't think that the NMR question wanted a the ppm chemical shifts of the compounds; it asked for the compound identification based on the peaks, their areas and the splitting patterns (something aimed at targetting the higher grade candidates ).

    Overall, I thought the paper was alright; lots on synoptic stuff (electronegativity, dipoles and bond polarities...), but there was stuff on reaction mechanisms which was alright. I didn't like the 4-mark maths question at the end though...:mad:
    lol what you trying to say... troolololol Saaaammme I was running outta time aswell so I put down loosely related chemistry equations in hope i would get method marks. Just to check for one of the questions did you write covalent, metallic and ionic bonding cause I wasted like 10 mins thinking over what the kinda bonding was lol. Helped alot that I resat F332 aswell =p Oh and thanks for the help on NMR it helped a lil lol...
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    (Original post by kinkin)
    lol what you trying to say... troolololol Saaaammme I was running outta time aswell so I put down loosely related chemistry equations in hope i would get method marks. Just to check for one of the questions did you write covalent, metallic and ionic bonding cause I wasted like 10 mins thinking over what the kinda bonding was lol. Helped alot that I resat F332 aswell =p Oh and thanks for the help on NMR it helped a lil lol...
    No problem
    For the bonding question, I put metallic, covalent, ionic in that order.
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    http://www.facebook.com/pages/Studen...69194713143309
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    So many of these.
 
 
 
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