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    (Original post by SaadKaleem)
    Do all the past papers, you should be good.

    when showing the formula of a product from the reaction of bromine & alkene for example, do we show OH aswell as Br or can we put Br twice as the double bond breaks?
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    (Original post by Zeekay98)
    when showing the formula of a product from the reaction of bromine & alkene for example, do we show OH aswell as Br or can we put Br twice as the double bond breaks?
    yeah we had to show the OH as well as the Br cuz the reaction was with bromine water...if it would have been bromine in CCl4 or any other non polar solute then we can put 2 Br when the double bond breaks
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    This is quite confusing guys, from all the past papers I've done so far, when it comes to the "separting funnel" question, the markscheme as well as the CGP would say that the aqueous layer is always in the lower part whereas the upper layer consists of impure halogenoalkane


    So why, in this question would they say the opposite, okay, yes the answer does makes sense, something that's heavy would usually be in the bottom, but in previous past papers it was the opposite as far as I could remember

    I'm afraid if this question comes up tomorrow even though it's easy, I wouldn't know which one the markscheme would want! :argh:


    :argh:
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    (Original post by Sumaiyya1999)
    yeah we had to show the OH as well as the Br cuz the reaction was with bromine water...if it would have been bromine in CCl4 or any other non polar solute then we can put 2 Br when the double bond breaks
    Hey,
    Out of interest, how did you manage studying all of AS Chemistry in just 4 months, (you're born in 1999 as your username suggests) so that got me wondering!
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    (Original post by Adorable98)
    Hey,
    Out of interest, how did you manage studying all of AS Chemistry in just 4 months, (you're born in 1999 as your username suggests) so that got me wondering!
    I didn't study all of AS chemistry in 4 months.....my school just makes us give unit 1 in jan and unit 2 and unit 3 in june
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    (Original post by Sumaiyya1999)
    I didn't study all of AS chemistry in 4 months.....my school just makes us give unit 1 in jan and unit 2 and unit 3 in june
    Oh, I see then!
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    (Original post by Adorable98)
    This is quite confusing guys, from all the past papers I've done so far, when it comes to the "separting funnel" question, the markscheme as well as the CGP would say that the aqueous layer is always in the lower part whereas the upper layer consists of impure halogenoalkane


    So why, in this question would they say the opposite, okay, yes the answer does makes sense, something that's heavy would usually be in the bottom, but in previous past papers it was the opposite as far as I could remember

    I'm afraid if this question comes up tomorrow even though it's easy, I wouldn't know which one the markscheme would want! :argh:


    :argh:
    CGP is wrong.

    If the organic compound has a density greater than 1.00 g/cm^3 then, it will be at the lower layer, if less than 1.00 g/cm^3, then it will at the upper layer.

    1.00 g/cm^3 is the density of water, (Aqueous layer)

    It also depends on what they're asking (The step) mentioned in the question.
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    (Original post by SaadKaleem)
    CGP is wrong.

    If the organic compound has a density greater than 1.00 g/cm^3 then, it will be at the lower layer, if less than 1.00 g/cm^3, then it will at the upper layer.

    1.00 g/cm^3 is the density of water, (Aqueous layer)

    It also depends on what they're asking (The step) mentioned in the question.
    Thaank you soo much, glad it came!!
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    What did you lot get for the value of x, I don't why I struggled with those 2 questions!
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    (Original post by Adorable98)
    What did you lot get for the value of x, I don't why I struggled with those 2 questions!
    X=8 for heating method and X=11 for Titration method.
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    (Original post by Adorable98)
    Thaank you soo much, glad it came!!
    Mhm, lucky you asked before
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    (Original post by SaadKaleem)
    X=8 for heating method and X=11 for Titration method.
    Okay so I got the first one right!!! :clap2: but not the second one!
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    (Original post by SaadKaleem)
    X=8 for heating method and X=11 for Titration method.
    what was the purpose of adding sodium hydrogen carbonate to iodoethane (I guess) ?? I was going to write because it will neutralise the acid BUT then I changed it and wrote to remove iodine?? Not sure, but I guess I saw a similar question in previous past papers..
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    (Original post by Adorable98)
    what was the purpose of adding sodium hydrogen carbonate to iodoethane (I guess) ?? I was going to write because it will neutralise the acid BUT then I changed it and wrote to remove iodine?? Not sure, but I guess I saw a similar question in previous past papers..
    And for the titration method! they said to write the molar mass of the hydrated crystallisation I wrote 124, is that right??
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    (Original post by Adorable98)
    what was the purpose of adding sodium hydrogen carbonate to iodoethane (I guess) ?? I was going to write because it will neutralise the acid BUT then I changed it and wrote to remove iodine?? Not sure, but I guess I saw a similar question in previous past papers..
    The acid, wasen't mentioned in the steps, but Sodium carbonate is a base, so its used to neutralize excess H+ ions, and that's what i wrote.

    (Original post by Adorable98)
    And for the titration method! they said to write the molar mass of the hydrated crystallisation I wrote 124, is that right??
    Eh, i don't remember. lol
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    (Original post by SaadKaleem)
    The acid, wasen't mentioned in the step, but Sodium carbonate is a base, so its used to neutralize excess H+ ions, and that's what i wrote.



    Eh, i don't remember. lol
    I see and what did you write for why was the hydrated washing soda (i guess) heated for 3 mins?? I wrote to remove excess water.. not sure??
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    (Original post by Adorable98)
    I see and what did you write for why was the hydrated washing soda (i guess) heated for 3 mins?? I wrote to remove excess water.. not sure??
    No idea, about that, i messed up those wierd type of questions.
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    What did you guys write as the chemical name for sodium carbonate??
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    (Original post by tanjimkhan)
    What did you guys write as the chemical name for sodium carbonate??
    I wrote bicarbonate soda , what did you write for why was the hydrated washing soda (i guess) heated for 3 mins?? I wrote to remove excess water.. not sure??
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    (Original post by Adorable98)
    I wrote bicarbonate soda , what did you write for why was the hydrated washing soda (i guess) heated for 3 mins?? I wrote to remove excess water.. not sure??
    I wanted to write about removing excess water.. but the question itself was of removing the excess water and that's done by the strong heating. I wrote "so that the crucible absorbs the heat before heating the washing soda"
 
 
 
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