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    how was it?
    i thouight it was ok, section A was piss easy
    the others were ok, little wierd
    i did questions 2 and 3, question 4 seemed impossible!
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    yea i did questions 1,2,3. They were all really easy, wot was the answer to y the SN1 reaction made it optically inactive??

    did u all get 6 for the water?
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    (Original post by rastaman)
    yea i did questions 1,2,3. They were all really easy, wot was the answer to y the SN1 reaction made it optically inactive??

    did u all get 6 for the water?
    lol that optically active one yes haha i didnt know wht i was saying so i kinda guessed but im sure ur right!
    and yes i got 6 for the water! woohoo!!
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    i thought it was really good, i did 1, 2 &3. did anyone here actually attempt 4? someone in my class did all three questions, cos they'd read that they give you the best two marks, but she didn't think she did very well on 4.
    i got six for the water as well.
    the replacement Q we did looked so much easier than the one we would have had 2 do!
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    yeh i did q 4, it was ok i dont know y everyone said it looked hard, didnt really look at 2, was it easy?
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    wow someone did question 4 hehe, congratulations you must be one of about 3 in the country
    I thought the paper was pretty generous really, got 6 for the water and 4.8% for percentage by volume of ozone in ozonised oxygen. I didn't realise there was a precise method for flame tests though, I just said stick the ****er in an open flame....
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    (Original post by emporium)
    Got 6 for the water and 4.8% for percentage by volume of ozone in ozonised oxygen....
    I got 6 for the water, and also got 4.8%. not 100% sure that's correct though as i thought my method was completely wrong.

    For 3c did people get C2H5CH=CH2, and for 2c(i) 2 moles hydrogen reacting with 1 mole of limonene?

    I wasn't sure about 1(a)i i put Ag+(s) + Cl-(g) goes to AgCl (s), though think that's wrong.
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    Both the ions are (aq).
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    was ag+ (aq) + cl- (aq) goes to AgCl (s)
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    That was so easy. I reckon the grade boundaries will be high- maybe 95% for an A?
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    Um, dont think they'll be THAT high
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    lol u serious?!?!?! I think the grade boundaries are gonna be slightly higher than last year
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    what were they last year? Is it including the coursework?
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    (Original post by DaveR)
    I got 6 for the water, and also got 4.8%. not 100% sure that's correct though as i thought my method was completely wrong.

    For 3c did people get C2H5CH=CH2, and for 2c(i) 2 moles hydrogen reacting with 1 mole of limonene?

    I wasn't sure about 1(a)i i put Ag+(s) + Cl-(g) goes to AgCl (s), though think that's wrong.
    those are the answers i got too! apart from the ionic equation one, where i put
    3Cl- (aq) + 3Ag+ (aq) ----> 3AgCl(s) cos there were three Cl- ions in the compound. don't know if that was right tho but it was only 1 mark!
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    Here are the answers:

    1a) Ag+(aq)+Cl-(aq) -------> AgCl(s)
    b) An excess to ensure all of the Cl- is precipitated
    c) x=6
    d) Flame test- lilac flame for potassium salt/ yellow flame for sodium chloride

    2a)Identify chiral centre on molecule as having four different groups surrounding carbon.
    b)SN1 mechanism/ trigonal planar intermediate so nucleophile can attack with equal facility from each side/ products formed in equal abundance so no overall optical activity.
    c) Cannot be distinguished using laboratory tests as both molecules contain the same functional groups
    d) NMR can identify molecules- A has less protons so lower integral value/ different proton environments
    e)Verify that 2 moles of hydrogen needed for each molecule reduced/ support this with a calculation (5*10^-3:1*10^-2 ratio)
    f) LiAlH4 cannot reduce the carbon carbon double bond as it is a nucleophile (the double bond is unreactive towards nucleophiles) although the Carbonyl group will be reduced.

    3a)4.8%
    b) Thermodynamic stability-products are at lower energy than reactants/ reaction would release energy were it kinetically unstable/
    Kinetic stabillity- activation energy requirements too high/ other factors contribute, e.g. steric hindrance or no available vacant orbitals as in the case of tetrachloromethane.
    c)Identify that area under graph represents total number of molecules/ area to the right of E(act) have sufficient activation energy/ catalyst lowers activation energy so the frequency of succesful collisions increase.
    d)but-1-ene.
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    it that your answers or did you ask your teacher or what?
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    (Original post by scarlet ibis)
    it that your answers or did you ask your teacher or what?

    These are what I think the answers are after discussing the paper with a friend, although neither of us did the last question.
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    damn i only messed up the liAlh4 one then... all the other answers are the same as mine... damn u sure about the lialh4?
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    i think i might have got that wrong too, but hey! it was only a 2 marker:rolleyes:
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    ur right about the LIALH4 thing cos it wont reduce the C=C bond as it isnt polar but will reduce the C=O bond

    i got it wrong 2
 
 
 

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