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Edexcel A2 Chemistry Exams -6CH04 (14th June) and 6CH05 (22nd June) Discussion Thread Watch

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    (Original post by samb1234)
    I don't think you want to tbh if it's from where I think it is
    You're tempting me to research this, brb.
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    hiya, could someone explain why the answer is A please? Quite confused
    thanks
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    I often get confused on questions where they tell us to find which option isnt a redox equation, like I know you figure out the oxidation numbers etc but for ex Q2 here, could someone please explain how they would come to the conclusion that its d? i thought it was B at first
    https://a5c076379da85d2c0b501a60f1a4...0Chemistry.pdf
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    (Original post by Neha121101)
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    hiya, could someone explain why the answer is A please? Quite confused
    thanks
    CO2 in solution forms carbonic acid
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    (Original post by C0balt)
    CO2 in solution forms carbonic acid
    oh ofc, thanks!
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    (Original post by Neha121101)
    oh ofc, thanks!
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    am i the only that actually enjoys unit 5 much more than unit 4? the maths is easier and the organic stuff you either know it or you don't it doesn't really try and trick you out. (maybe that's just me lol)
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    I don't get 12 as the answer is b but surely London forces cant be stronger then hydrogen bonds


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    (Original post by alexfrances)
    am i the only that actually enjoys unit 5 much more than unit 4? the maths is easier and the organic stuff you either know it or you don't it doesn't really try and trick you out. (maybe that's just me lol)
    Yeah, probs just u lol
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    (Original post by setarcos)
    Yeah, probs just u lol
    Lol unit 5 is horrible


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    (Original post by Supermanxxxxxx)
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    I don't get 12 as the answer is b but surely London forces cant be stronger then hydrogen bonds


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    benzene has such a large number of electrons compared to ethanol that the london forces in this case are stronger than the hydrogen bonds of the ethanol. (that's the extent of my knowledge tbh)
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    (Original post by Supermanxxxxxx)
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    I don't get 12 as the answer is b but surely London forces cant be stronger then hydrogen bonds


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    Benzene has 6 electrons that are delocalised and as such can set up stronger temporary dipoles much more easily than most molecules
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    How is this C?
    I put B as one mole reacts with 2 moles of AgNO3 so two moles of AgCl should form, so there should be 2 Cl in the complex, or am I missing something completely obvious?
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    Is anyone able to help me understand why the answer to 11 is C? Thanks Name:  image.jpg
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    (Original post by Peppercrunch)

    How is this C?
    I put B as one mole reacts with 2 moles of AgNO3 so two moles of AgCl should form, so there should be 2 Cl in the complex, or am I missing something completely obvious?
    Oops didn't realise you just asked about the same question!
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    (Original post by Peppercrunch)

    How is this C?
    I put B as one mole reacts with 2 moles of AgNO3 so two moles of AgCl should form, so there should be 2 Cl in the complex, or am I missing something completely obvious?
    Theres 3Cl in the compound (crystals)
    only the free Cl- ions OUTSIDE the complex react with AgNO3
    so you're right in that 2 moles of AgCl form
    therefore there must be only 1 Cl in the complex
    I don't know if that makes sense lol but I hope that helps
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    (Original post by PythagorasRex)
    Oops didn't realise you just asked about the same question!
    Haha, doing the same past paper. It really annoyed me as there was a question with bad wording.

    (Original post by Neha121101)
    Theres 3Cl in the compound (crystals)
    only the free Cl- ions OUTSIDE the complex react with AgNO3
    so you're right in that 2 moles of AgCl form
    therefore there must be only 1 Cl in the complex
    I don't know if that makes sense lol but I hope that helps
    Ah, thank you. It did make sense to me. It is a bit hard to explain.
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Size:  20.6 KBDoes anyone know why the enthalpy of cyclohexane is lower than the enthalpies of X (cyclohex1ene) and benzene? I get that benzene is more stable than X because of its delocalised ring of electrons hence it has a lower enthalpy, but why does it have a lower enthalpy than cyclohexane?
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    (Original post by PythagorasRex)
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Size:  20.6 KBDoes anyone know why the enthalpy of cyclohexane is lower than the enthalpies of X (cyclohex1ene) and benzene? I get that benzene is more stable than X because of its delocalised ring of electrons hence it has a lower enthalpy, but why does it have a lower enthalpy than cyclohexane?
    Structure X in that question isn't cyclohex-1-ene. It's the kekule structure if you read again carefully. The kekule structure has 3 C=C bonds so has a higher enthalpy than cyclohexane.

    Benzene has a higher enthalpy than cyclohexane as shown in that diagram.
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    How do you know which separation technique is needed for organic synthesis questions? I know there's Simple Distillation, Steam Distillation, Solvent Extraction and Recrystallisation...
 
 
 
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