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    Anyone wanna join me in an all nighter for this exam?
    Knowing someone else is doing it will make it soo much easier to do
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    (Original post by Adam9)
    I personally do not use chemical storylines ... I use a revision guide (cgp) that covers everything I need to know from storylines and chemical ideas.

    But generally, you gain nothing from storylines
    Hmm, that's what I did for AS but my teacher said they're running out of questions to ask so they're using storylines more :/ also, i'm doing past papers and there's a bit of storylines not covered in the revision guide
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    (Original post by beckyxo)
    What does that mean? (Sorry) Bx
    I think its to do with fertilisers from the crops running off into a body of water and causing rapid growth of algae which takes oxygen away from fish and kills them. I don't think we need to know what it means though I think you still get the marks if you write it down or just write down run off.


    Also I've found this site:
    http://www.4college.co.uk/a/index2.php
    its quite good and it has the toolkits on them
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    (Original post by mooniibuggy)
    Hmm, that's what I did for AS but my teacher said they're running out of questions to ask so they're using storylines more :/ also, i'm doing past papers and there's a bit of storylines not covered in the revision guide
    My teacher advised giving them a passing glance before the exam, but overall the questions are on your chemical knowledge (as they should be =P) with some storylines aspects hidden in there.
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    (Original post by mooniibuggy)
    Hmm, that's what I did for AS but my teacher said they're running out of questions to ask so they're using storylines more :/ also, i'm doing past papers and there's a bit of storylines not covered in the revision guide
    the salters revision guide tells you the parts of storylines it doesnt cover.. so you could just read those parts
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    In a few past papers I have come across questions similar and don't understand why the answer is what it is!

    In a question such as
    CH3OH(g) <=> HCHO(g) + H2 /\H = +80KjMol-1

    It asks what the effect of raising the temperature would be on yield of HCHO.
    I thought it would reduce the yield, as raising temperature favours the endothermic reaction, which is the reverse reaction, shifting equlibrium left.

    However, the mark sheme says yield increases, as equilibrium moves in the endothermic direction.

    Can someone please explain why this is the answer. :confused:

    Thanks
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    So what do you guys recommend doing at this stage? Reading the revision guide and doing past paper questions?
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    (Original post by tkoki1993)
    sorry I dont have the CGP... they try to make too many jokes and it just annoys me
    lol very truee.. thank you anyway
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    (Original post by RayM)
    In a few past papers I have come across questions similar and don't understand why the answer is what it is!

    In a question such as
    CH3OH(g) <=> HCHO(g) + H2 /\H = +80KjMol-1

    It asks what the effect of raising the temperature would be on yield of HCHO.
    I thought it would reduce the yield, as raising temperature favours the endothermic reaction, which is the reverse reaction, shifting equlibrium left.

    However, the mark sheme says yield increases, as equilibrium moves in the endothermic direction.

    Can someone please explain why this is the answer. :confused:

    Thanks
    The forward reaction to the right in endothermic, a postive enthalpy change means it is endothermic because it needs to take energy in. So the equilibrium favour the endothermic reaction but that is to the right so the yield will increase.
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    (Original post by limetang)
    My teacher advised giving them a passing glance before the exam, but overall the questions are on your chemical knowledge (as they should be =P) with some storylines aspects hidden in there.
    oops, looks like i'm overworking myself xD i'm becoming too paranoid and revising everything in detail.

    (Original post by tkoki1993)
    the salters revision guide tells you the parts of storylines it doesnt cover.. so you could just read those parts
    i *just* saw that! i don't normally look at that part in detail lol, yeah it does state the sections we're examined on in the revision guide thanks
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    (Original post by RayM)
    In a few past papers I have come across questions similar and don't understand why the answer is what it is!

    In a question such as
    CH3OH(g) &lt;=&gt; HCHO(g) + H2 /\H = +80KjMol-1

    It asks what the effect of raising the temperature would be on yield of HCHO.
    I thought it would reduce the yield, as raising temperature favours the endothermic reaction, which is the reverse reaction, shifting equlibrium left.

    However, the mark sheme says yield increases, as equilibrium moves in the endothermic direction.

    Can someone please explain why this is the answer. :confused:

    Thanks
    because the forward reaction is endothermic...endothermic is bond breaking and so if u look at the forward reaction its breaking the bonds..
    hope this helps..i think its right
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    (Original post by mooniibuggy)
    oops, looks like i'm overworking myself xD i'm becoming too paranoid and revising everything in detail.



    i *just* saw that! i don't normally look at that part in detail lol, yeah it does state the sections we're examined on in the revision guide thanks
    Well better being paranoid than being too laid back (like me).
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    ohh right our teacher called it leaching, eutrophication sounds better!
    ahh bad times!!
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    (Original post by plod2)
    Also I've found this site:
    http://www.4college.co.uk/a/index2.php
    its quite good and it has the toolkits on them

    Ah that websites so good! Thanks!
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    (Original post by limetang)
    Well better being paranoid than being too laid back (like me).
    You have a university offer to meet!!!

    (maybe?)
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    (Original post by Jamesrb)
    So what do you guys recommend doing at this stage? Reading the revision guide and doing past paper questions?
    i'm finishing off oceans and then past papers for the whole day tomorrow
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    (Original post by mooniibuggy)
    i'm finishing off oceans and then past papers for the whole day tomorrow
    When you say finishing off, do you mean reading? From CI?
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    Kp so partial pressures is Not on the specification anymore right?
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    (Original post by mooniibuggy)
    You have a university offer to meet!!!

    (maybe?)
    I know I know.
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    Does anyone know why ions dissolve in water or polar solvents? is it to do with ionic lattice breaking up and ion-dipoles are forming? if this is the case, how do i expand on it?

    also do we need to know about colourfastness?
 
 
 
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