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    Woooo! In 7 hrs and 35 mins, we will be freeeeeeeeeeeeeeeeeeeee! :')
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    guys how would you react half equation for this equation Q7b

    http://www.a-levelchemistry.co.uk/AQ...W-QP-Jun10.pdf thanx alot
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    (Original post by al_habib)
    guys how would you react half equation for this equation Q7b

    http://www.a-levelchemistry.co.uk/AQ...W-QP-Jun10.pdf thanx alot
    From the question, we know that the emf of the reaction is +2.91 V.

    Using the value from the table that Li+ + e- ---> Li = -3.04 V, we know that

    E(positive electrode) - -3.04 = 2.91, that is, E(positive electrode) + 3.04 = 2.91.

    2.91 - 3.04 = -0.13 V = E(positive electrode)
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    (Original post by Jin3011)
    I'm not as prepared as I was for unit 4. So I think maybe 100ums If I'm lucky.
    How about you?
    I good B probably. I wanted an A* overall but this exam clearly wasn't having it lol
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    Guys, look at the answer for 7c) in this mark scheme. http://www.scribd.com/doc/50819775/A...11-Mark-Scheme

    It says [Al(OH)6]3- when NaOH is added in excess (QP- http://www.scribd.com/doc/50819577/A...y-January-2011 if you need)

    In the textbook it says when you add OH- in excess you get [Al(OH)4]- (p243 of the official nelson thornes one)
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    I went to bed and just woke up...I wonder why :rolleyes:

    my 12:00 we'll be free from the bondage's of AQA!!
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    Which one is correct?
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    (Original post by T-Toe)
    I went to bed and just woke up...I wonder why :rolleyes:

    my 12:00 we'll be free from the bondage's of AQA!!
    I take it you didn't pick chemistry based subject at uni? I didn't. I won't ever see chemistry again in my life. Hopefully...
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    (Original post by joseph2008)
    I take it you didn't pick chemistry based subject at uni? I didn't. I won't ever see chemistry again in my life. Hopefully...
    LOL I did :ninja: However it won't be endorsed by crappy AQA :P
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    (Original post by joseph2008)
    Which one is correct?
    My dad's a former chemist and insomniac. He says that [Al(OH)4]- should be produced, and that the mark scheme is incorrect (unless the question is a specific case that we aren't aware of)
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    (Original post by joseph2008)
    Which one is correct?
    I'd say stick with [AL(OH-)6]3-

    I've learnt to not question AQA's mark schemes.. or they'll be price to pay lol
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    Where does it say on the mark scheme?
    All I saw was [cr(oh)6]^3-
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    (Original post by Jin3011)
    Where does it say on the mark scheme?
    All I saw was [cr(oh)6]^3-
    Talking to me?

    6b)

    EDIT: Sorry, I said the wrong question before, its 6b not 7c. Check out 6b.
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    Thats really awkward. All I've ever known is oh4 not oh6. Wikipedia says this Aluminium hydroxide is amphoteric. It dissolves in acid, forming Al(H2O)63+ (hexaaquaaluminium(3+)) or its hydrolysis products. It also dissolves in strong alkali, forming Al(OH)4- (tetrahydroxidoaluminate(1-)).
    No mention of any oh6

    But weirdly enough, they've got this http://www.wikichemistry.com/konfuci...nium+hydroxide

    Why does everything have to contradict itself =[
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    (Original post by Jin3011)
    Thats really awkward. All I've ever known is oh4 not oh6. Wikipedia says this Aluminium hydroxide is amphoteric. It dissolves in acid, forming Al(H2O)63+ (hexaaquaaluminium(3+)) or its hydrolysis products. It also dissolves in strong alkali, forming Al(OH)4- (tetrahydroxidoaluminate(1-)).
    No mention of any oh6
    Yup. I'm confused now. Which idiot puts one thing in their official book then something else in their own mark scheme?
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    (Original post by joseph2008)
    Yup. I'm confused now. Which idiot puts one thing in their official book then something else in their own mark scheme?
    I know. Those 1-2 marks could be the difference between a whole grade.
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    (Original post by Jin3011)
    I know. Those 1-2 marks could be the difference between a whole grade.
    I was looking at a sheet which my teacher personally wrote and photocopied. It says OH4. I'm gonna go with what she said.
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    (Original post by joseph2008)
    Yup. I'm confused now. Which idiot puts one thing in their official book then something else in their own mark scheme?
    AQA - proud to make students suffer, or possible just incapable of proof reading and complacently incompetent.

    Just have to hope the question doesn't come up as I now have no idea which to put if it did. Oh well, at least it's nearly over.
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    (Original post by joseph2008)
    I was looking at a sheet which my teacher personally wrote and photocopied. It says OH4. I'm gonna go with what she said.
    I wrote oh4 in my mock and my teacher marked it wrong
    And it's what she taught us as well.
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    this exam gonna be great, ill tell u lot my answers afterwards lol
 
 
 
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