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    (Original post by phaggatron5001)
    Isn't iodine insoluble? Isn't it bromine that would turn the solution a red/brown color? I said a grey solid would form on the anode.
    If I'm honest I'm going off what you guys are asking I cannot even remember the question? Bromine then, same goes, same group ect. Different result. Sorry you're right it was on Bromine I believe.
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    Sounds like I messed this exam up guys. God bless.
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    (Original post by Elliottmanwaring)
    If I'm honest I'm going off what you guys are asking I cannot even remember the question? Bromine then, same goes, same group ect. Different result. Sorry you're right it was on Bromine I believe.
    No it was sodium iodide and sodium chloride. I remember the question after asked for it s reaction with AgNO3 and then with aqueous ammonia, then there was a calculation asking for the percentage of sodium iodide in the mixture.
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    (Original post by RasputinReborn)
    No it was sodium iodide and sodium chloride. I remember the question after asked for it s reaction with AgNO3 and then with aqueous ammonia, then there was a calculation asking for the percentage of sodium iodide in the mixture.
    Oh yeah! Fair play beside the question of the Flouridated water, this was one if the hardest calculations. I definitely got both of those questions wrong!
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    (Original post by Elliottmanwaring)
    Oh yeah! Fair play beside the question of the Flouridated water, this was one if the hardest calculations. I definitely got both of those questions wrong!
    Missed out the fluoride calculation(ran out of time). Got 48.0% for the mixture. I think for the AgNO3 reaction, I cocked up I said a White precipitate and yellow precipitate will form since there were Cl- ions and I- ions, and when ammonia solution is added, the White precipitate dissolves and the AgI remains. Can you actually have 2 precipitations?
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    (Original post by Elliottmanwaring)
    As I said, I'm no pro but I would assume the marks are for:
    1. Chlorine is a more powerful oxidising agent than Iodine so it liberates the iodine.
    2. 2I- ---> I2 + 2e-
    3. Solution turns dark red/brown colour and an explanation of basically what the equation is telling you in terms of movement of electrons.

    That's what I put but I'm not sure if that is on the mark scheme.
    After comparing answers most of the stuff I've done is wrong I think 😢
    I'm most likely going to re sit CH1 but CH2 is what I prefer so yeh. Is anyone else in the same boat as me or?
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    (Original post by ChemSinceDaay...)
    After comparing answers most of the stuff I've done is wrong I think 😢
    I'm most likely going to re sit CH1 but CH2 is what I prefer so yeh. Is anyone else in the same boat as me or?
    Me and 99% of Wales. There were no definition questions, no equilibria questions (excluding Kc and the concentration calculation) and only 3 marks on ionisation energies. This was a maths exam that was harder than C1 and C2...


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    (Original post by RasputinReborn)
    Me and 99% of Wales. There were no definition questions, no equilibria questions (excluding Kc and the concentration calculation) and only 3 marks on ionisation energies. This was a maths exam that was harder than C1 and C2...
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    Yeh, but this is a new spec so we should've expected a very bad paper so I think that next year will be more better because they'll include definitions, Kc, equilibria etc. Also actual calculations that we've done in class. I wish we done AQA because WJEC are *********!
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    0.27 was your answer for the equilibrium question?
    (Original post by RasputinReborn)
    Me and 99% of Wales. There were no definition questions, no equilibria questions (excluding Kc and the concentration calculation) and only 3 marks on ionisation energies. This was a maths exam that was harder than C1 and C2...


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    (Original post by Elliottmanwaring)
    0.27 was your answer for the equilibrium question?
    I got something around 4, but I'm probably wrong 😂


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    (Original post by RasputinReborn)
    I got something around 4, but I'm probably wrong 😂


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    Does anyone know what iodine clock reactions is?
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    (Original post by Elliottmanwaring)
    0.27 was your answer for the equilibrium question?
    I had 0.27 too but I don't really know how
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    (Original post by RasputinReborn)
    I got something around 4, but I'm probably wrong 😂


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    I got 4. something!! I found this paper really hard, most definitely resisting chemistry and possibly biology, WJEC have made their AS exams disgusting this year.
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    hey guys, will i get marks deducted for answer in incorrect significant figures, not those extreme one like 7 or 8 figures after decimal but like 2 to 3? Im frustrated about that because my teachers never care about it in tests and my frds said it have to depends on the smallest s.f. given in the question. HELP!!!!
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    (Original post by matthewyakgw)
    hey guys, will i get marks deducted for answer in incorrect significant figures, not those extreme one like 7 or 8 figures after decimal but like 2 to 3? Im frustrated about that because my teachers never care about it in tests and my frds said it have to depends on the smallest s.f. given in the question. HELP!!!!
    Well if in the question it states to specific sf then u must give it in that form. However if it's not stated then u don't have to because examiners will consider ecf (error carried forward) so they should give u the mark if reasonable.

    Anyways how did u find the exam overall, I found it really damn hard so I'll be re sitting this and hopefully scoring high in my favourite CH2.
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    (Original post by ChemSinceDaay...)
    Well if in the question it states to specific sf then u must give it in that form. However if it's not stated then u don't have to because examiners will consider ecf (error carried forward) so they should give u the mark if reasonable.

    Anyways how did u find the exam overall, I found it really damn hard so I'll be re sitting this and hopefully scoring high in my favourite CH2.
    so will i get marks deducted because i check some past paper mark scheme and they said cao [3] which means only all 3 marks forcorrect answer only, so will i get all the marks or lose one mark. this exam had so xxxxxxx many calculations, if i get one mark deducted from every single calculation, i would pretty sad.
    lol should i send an email to wjec?

    i find some calculations are really complex and quite new to us but i should be alright if no mark deducted for incorrect s.f. because in my memory there are no question stated need specific s.f.
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    (Original post by matthewyakgw)
    so will i get marks deducted because i check some past paper mark scheme and they said cao [3] which means only all 3 marks forcorrect answer only, so will i get all the marks or lose one mark. this exam had so xxxxxxx many calculations, if i get one mark deducted from every single calculation, i would pretty sad.
    lol should i send an email to wjec?

    i find some calculations are really complex and quite new to us but i should be alright if no mark deducted for incorrect s.f. because in my memory there are no question stated need specific s.f.
    As mentioned above, you will only be deducted one mark if it's EXPLICITLY stated. Didn't the relative atomic mass of Si require certain significant figures? I can't quite remember.
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    (Original post by Luketidley)
    I got 4. something!! I found this paper really hard, most definitely resisting chemistry and possibly biology, WJEC have made their AS exams disgusting this year.
    Don't jump to rash conclusions yet. Everyone after both exams found them very difficult. Even on TSR, people found these tough. CH2 last year was 66% for an A, which is low, but that paper was easier than our CH1 paper , so I suspect ours could be in low 60s/ high 50s.

    BY1 in 2010 required 59% for an A, 59! I don't think we're screwed, yet.
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    (Original post by RasputinReborn)
    As mentioned above, you will only be deducted one mark if it's EXPLICITLY stated. Didn't the relative atomic mass of Si require certain significant figures? I can't quite remember.
    i dont think they did mention
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    (Original post by matthewyakgw)
    i dont think they did mention
    Yes that questions did require 3sf I remember

    It was 28/29/30 Si
    28=91.6 29=5.6%. 30=2.8%
    (28x91.6)+(29x5.6)+(30x2.8)
    Divide by 100
    =28.112
    3sf=28.1% that's what I wrote
 
 
 
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