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    (Original post by ABCDemily)
    I had a quick count and managed to drop at least 25, just through pure lack of knowledge and the others not being as detailed as they should have been. Not good!

    I have an English Lit exam tomorrow morning. I need to get off TSR.
    Me too!
    what texts are you doing?
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    (Original post by tom108)
    anyone know what the answer was to when we had to draw a curly arrow to show the momevment of electrons for one mark?

    And what was the answer to 'why is CH2CLCH3BR formed wheras CH2CLCH2CL not formed when solution is mixed in NAOH.???
    I put that since NaCl is not an electrophile (Cl- in solution cannot attack the electron-dense C=C bond; it is a nucleophile), Br2 must attack ethene first. After the intermediate carbocation forms with 1 Br atom, either Br- can add or NaCl can supply the Cl- which can easily bond at this point.

    I can't remember about the curly arrow though : /
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    (Original post by tom108)
    anyone know what the answer was to when we had to draw a curly arrow to show the momevment of electrons for one mark?

    And what was the answer to 'why is CH2CLCH3BR formed wheras CH2CLCH2CL not formed when solution is mixed in NAOH.???
    It was why isnt CH2ClCH2Cl formed when its mixed in a solution of sodium chloride. Because the guy initially made it in a mixture of NaCl and Br2.

    Sodium chloride contains Cl- ions, I said these are not electrophiles but nucleophiles as they have a negative charge and lone pair. the mechanism in the question was electrophilic addition across an alkene. So the chlorinated molecule wouldnt be made because there were no Cl2 or Cl+ present in the solution to undergo electrophilic addition. The Br2 gets a dipole induced in it and splits to form Br+, which was the attacking electrophile.

    Me thinks?!
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    (Original post by Tetanus)
    What did everyone get for the mass? I got 12g.

    I got it through n = V x C / 1000 then n = m / Mr??
    I did exactly the same, but apparantly the answer is 19
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    well that was a ****ing hard paper.

    for the first page did you guy get these answers?

    2. phenylamine
    3. electrophillic addition


    and there was couple of questions on bonding of molecules i got (in this order)
    metallic
    covalent
    ionic

    the -O- fuctional group I wrote ester, but after consulting the data sheet i got ether (tells you ether is C-O and ester is COO)

    also for the sulphur page I got the following:

    a S atom with 6 F's around it, in a octohedral shape bond angle 90'. for dot cross i put one x on each and one o on each, so 12 overall.

    um deltasurr was consufing, i got 3 MILLION joules when x1000 made me think twice lol.. but in the end i got -268+9somethingthousand which gave like 97 or 99700.1 i think cant remember exactly.

    um energy levels is pretty simple, pretty much 6 marks each year.
    glad electrophiles came up, easy definition - positive ion which reacts by accepting a lone pair of electrons to form a covalent bond..

    nmr i got CH3-CBr2H so a C with 3H's another C, with the two Br2 atoms on THIS and the H on the last space at the end..

    edit:

    same with buffers - rresist changes in ph when small amounts of alkali or acid are added to the solution..

    can someone clarify the conj. acid for me? I put H2So4- as the acid, but people put H+?
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    Question 1
    Organic compound: phenyl amine

    Structure: 1,3-dimethly amine

    Condition: temperature below 5 degrees (ice-cold)

    Reaction mechanism: electrophillic substituition

    Witts prediction: Anyone.!

    Why dyes are coloured:
    electron is excited / jumps up energy levels AND (as a result of) light / (UV) radiation / energy / photons
    frequency (absorbed) depends on energy change
    OR (?)E = hv
    dyes / coloured compounds / ‘compounds containing more benzene rings’ (AW) absorb in the visible / absorb light
    plus two from:
    energy levels are closer / energy gap is smaller / excitation energy is smaller when there is: more delocalisation more conjugation more than one benzene ring
    larger chromophore
    (dyes) transmit / reflect (NOT emit) the complementary colour ??



    Explain why benzene undergoes substitution: maintain stability, delocalised electrons keep the benzene ring intact and what else??

    Total : 16 marks
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    upload a copy of the paper anyone?
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    Im doing up a markscheme. so at the end we shall have an unoffical mark scheme
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    (Original post by Mr.Messy)
    well that was a ****ing hard paper.

    for the first page did you guy get these answers?

    2. phenylamine
    3. electrophillic addition


    and there was couple of questions on bonding of molecules i got (in this order)
    metallic
    covalent
    ionic

    the -O- fuctional group I wrote ester, but after consulting the data sheet i got ether (tells you ether is C-O and ester is COO)

    also for the sulphur page I got the following:

    a S atom with 6 F's around it, in a octohedral shape bond angle 90'. for dot cross i put one x on each and one o on each, so 12 overall.

    um deltasurr was consufing, i got 3 MILLION joules when x1000 made me think twice lol.. but in the end i got -268+9somethingthousand which gave like 97 or 99700.1 i think cant remember exactly.

    um energy levels is pretty simple, pretty much 6 marks each year.
    glad electrophiles came up, easy definition - positive ion which reacts by accepting a lone pair of electrons to form a covalent bond..

    nmr i got CH3-CBr2H so a C with 3H's another C, with the two Br2 atoms on THIS and the H on the last space at the end..
    Phenylamine is correct.
    I think it was electrophilic substitution since there was a hydrogen atom on the benzene ring initially.

    The bonds sound right although I don't remember very well.

    C-O-C is ether because ester needs a C=O bond in it.

    SF6 sounds right. There is a picture of the correct 3D shape here http://www.chm.bris.ac.uk/motm/SF6/SF6h.htm

    -268ish for Ssys sounds right. I think Stot was +9799 or thereabouts.

    Your electrophile and nmr answers looks right too.
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    (Original post by Mr.Messy)
    well that was a ****ing hard paper.

    for the first page did you guy get these answers?

    2. phenylamine
    3. electrophillic addition


    and there was couple of questions on bonding of molecules i got (in this order)
    metallic
    covalent
    ionic

    the -O- fuctional group I wrote ester, but after consulting the data sheet i got ether (tells you ether is C-O and ester is COO)

    also for the sulphur page I got the following:

    a S atom with 6 F's around it, in a octohedral shape bond angle 90'. for dot cross i put one x on each and one o on each, so 12 overall.

    um deltasurr was consufing, i got 3 MILLION joules when x1000 made me think twice lol.. but in the end i got -268+9somethingthousand which gave like 97 or 99700.1 i think cant remember exactly.

    um energy levels is pretty simple, pretty much 6 marks each year.
    glad electrophiles came up, easy definition - positive ion which reacts by accepting a lone pair of electrons to form a covalent bond..

    nmr i got CH3-CBr2H so a C with 3H's another C, with the two Br2 atoms on THIS and the H on the last space at the end..

    edit:

    same with buffers - rresist changes in ph when small amounts of alkali or acid are added to the solution..

    can someone clarify the conj. acid for me? I put H2So4- as the acid, but people put H+?
    I got exactly the same answers as you - except i wrote ether instead of ester and i got elctrophilic substitution
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    (Original post by ManPowa)
    Question 1
    Organic compound: phenyl amine

    Structure: 1,3-dimethly amine

    Condition: temperature below 5 degrees (ice-cold)

    Reaction mechanism: electrophillic substituition

    Witts prediction: Anyone.!

    Why dyes are coloured:
    electron is excited / jumps up energy levels AND (as a result of) light / (UV) radiation / energy / photons
    frequency (absorbed) depends on energy change
    OR (?)E = hv
    dyes / coloured compounds / ‘compounds containing more benzene rings’ (AW) absorb in the visible / absorb light
    plus two from:
    energy levels are closer / energy gap is smaller / excitation energy is smaller when there is: more delocalisation more conjugation more than one benzene ring
    larger chromophore
    (dyes) transmit / reflect (NOT emit) the complementary colour ??



    Explain why benzene undergoes substitution: maintain stability, delocalised electrons keep the benzene ring intact and what else??

    Total : 16 marks
    I put temp below 5 and alkali conditions.
    Didnt the two colours mix to from a orange colour?

    For the six marker, that sounds perfect!!

    Other answers i remember writing?

    Ether
    Alkene
    Ringing a COOH
    The reason we add salts,? So that the molecule is soluble in water.

    Can you remmeber Q 2?
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    (Original post by ManPowa)
    Question 1
    Organic compound: phenyl amine

    Structure: 1,3-dimethly amine

    Condition: temperature below 5 degrees (ice-cold)

    Reaction mechanism: electrophillic substituition

    Witts prediction: Anyone.!

    Why dyes are coloured:
    electron is excited / jumps up energy levels AND (as a result of) light / (UV) radiation / energy / photons
    frequency (absorbed) depends on energy change
    OR (?)E = hv
    dyes / coloured compounds / ‘compounds containing more benzene rings’ (AW) absorb in the visible / absorb light
    plus two from:
    energy levels are closer / energy gap is smaller / excitation energy is smaller when there is: more delocalisation more conjugation more than one benzene ring
    larger chromophore
    (dyes) transmit / reflect (NOT emit) the complementary colour ??



    Explain why benzene undergoes substitution: maintain stability, delocalised electrons keep the benzene ring intact and what else??

    Total : 16 marks

    thanks for the post could you do this for all the questions please?
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    (Original post by jiemanm10)
    thanks for the post could you do this for all the questions please?
    What was question 2 about?I'll remember a few..
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    (Original post by tom108)
    What was question 2 about?I'll remember a few..
    sorry, i honestly couldnt tell you, my mind's just gone blank! to be honest any questions you can remember would be helpful thanks
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    You know the question on the oxidation states. Wasnt fluorine being reduced from -1 to -4 ???
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    (Original post by tom108)
    You know the question on the oxidation states. Wasnt fluorine being reduced from -1 to -4 ???
    Flourine is always -1.

    It was 3S + 2CuF2 --> 2CuS + SF4 I think.

    We were told that copper is +2 to start with.

    Sulfur goes from 0 in 3S to +4 in SF4. (oxidation)

    Apparently sulfur also gets reduced: 0 to -2 in CuS.

    I erroneously wrote copper gets reduced from +2 in CuF2 to -4 in CuS >_> now I think of it, copper can't be a -4 ion so both answers were sulfur. In CuS the states are +2 and -2.
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    (Original post by jungdao)
    Flourine is always -1.

    It was 3S + 2CuF2 --> 2CuS + SF4 I think.

    We were told that copper is +2 to start with.

    Sulfur goes from 0 in 3S to +4 in SF4. (oxidation)

    Apparently sulfur also gets reduced: 0 to -2 in CuS.

    I erroneously wrote copper gets reduced from +2 in CuF2 to -4 in CuS >_> now I think of it, copper can't be a -4 ion so both answers were sulfur. In CuS the states are +2 and -2.
    2 marks gone for me
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    (Original post by tom108)
    2 marks gone for me
    D: I've counted 13 lost for definite, for me.
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    (Original post by jungdao)
    D: I've counted 13 lost for definite, for me.
    So far, about 9 for me. That will soon change....
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    Question 2

    Oxidation and reduction (4 marks) Not sure!!!

    Equation: sulfur tetrafluoride plus oxygen to form sulfur hexafluoride

    Electron configuration: 1s2 2s2 2p6 3s2 3p4

    Dot and cross for SF6: 6 groups of electrons around the central sulfur atom.. one electron from sulfur and one from fluorine. 3 lone pairs on each fluorine atom.

    3D shape of Sf6 and a bond angle of 90 degrees.

    Mass of lithium: 112 KG

    Systematic name for Li2S: Lithium sulfide

    Bonding:
    Lithium - metallic
    Sulfur trioxide - covalent
    lithium fluoride : ionic

    Explain why SF6 is a gas at room temperature while hexanedioic acid is a solid: Answer people/!!!

    Entropy change of system (2)

    Total entropy change (2)

    Formula of potassium chlorate(VII) - I Put KCLO4 - the clorine has a an oxidation state of 7

    Comment - If your total entropy was positive, then a fuse will not be required as the reaction is spontaneous. However, if your toral entropy change was negative, then a fuse will be required. I think on the mark scheme, this will be ECF as even if you get the wrong answer but you can still get the mark for the comment.

    29 marks
 
 
 
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