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    (Original post by Nechromatic)
    29.5% is what I got aswell
    I got 35.something %
    So you had the mass of BaSO4 (the white precipitate).
    Divide by Mr of BaSO4 (233.4)
    This gives you moles x

    The reaction was this:

    BaCl2 + H2SO4 --> BaSO4 + 2HCl

    Meaning the number of moles of BaCl2 is also x
    Multiply x by Mr of BaCl2 (208.3) to get mass of BaCl2 (y)

    Percentage of MgCl2 therefore:

    [(1.506-y)/1.506]*100

    I am just using 1.506 randomly, I can't remember what the total mass of both MgCl2 and BaCl2 was, but the above is the method.
    And I got 35.something % from this method.
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    Omg I literally feel the same way
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    I got 35.5%

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    Yes it did hahahahaha
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    (Original post by desigenius)
    I got c3h8
    What did you guys put for the question about how to reduce the error in the titration??
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    (Original post by Izzy6785)
    What did you guys put for the question about how to reduce the error in the titration??
    Increase the volume measured so that %error/volume measured x 100 is smaller
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    (Original post by SANTR)
    Have you seen the last 5-7 years grade boundaries, it never falls below 80%
    Before lowering peoples hopes you should really invest some time doing actual research rather then plucking random 'facts'.

    you said the last 5-7 years grade boundries never fell below 80? lmao do some research

    Actual facts : unit 1 chem had gone below 80% for an A a few rimes before, but by much , around 77%, however we have to also take into account unit 2 chem, as our exam today was a mix of last year unit 1 and 2. And unit 2 chem has sometimes gone as low as 67% for a A .

    Therefore, with all due respect please stop putting hopes down, grade bounrdies should most definetly go down. And the issue here isn't wehter they will or not, its just a matter of false information provided to the many people reading this thread.

    Think before you speak, and don't fabricate facts.
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    (Original post by Asad_2015)
    Guys it was a hard exam, and I'm saying this because a lot of you are worried. Don't be, all we can do is revise for the next one now. I know it's hard to get your mind off it but i know everyone and including me have worked our socks off, we can't turn the clock back, we wish we could but we can't. What I'm saying is that it's half term now, so guys just take 2/3hrs rest, every single one of us deserves a bit of rest These exams are turning us into robotic like things :s It's always better to keeping walking forward than walking back all the way and realising, nothing is left...

    Predictions A: 55-58/80, B: 48/80, C: 39/80
    Aw love this!! It's true though we have worked too hard 😌😌
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    Ugh, I agree with every single one of you. Worst part is this paper isn't a very hard one and you know the stuff but somehow you panic and you decide to plug wrong numbers in (wrong Mr for BaSO4 because I read the periodic table wrongly , forgot to subtract the volume of flask P, used the wrong titre value) lol I hope there are method marks :/ do you guys think they'll give method marks??
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    (Original post by dobson123)
    Did anyone else completely run out of time? I had about 5 minutes to do all the multiple choice.....
    sooo mee though some of them i was like look at question ookk guess
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    (Original post by The Panic Queen)
    Aw love this!! It's true though we have worked too hard 😌😌
    ikr, we can't let some random aqa exam board break our momentum :P we are warriors:auto::banana2:now lets boogey XD
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    (Original post by mbb123mbb)
    I got 35.something %
    So you had the mass of BaSO4 (the white precipitate).
    Divide by Mr of BaSO4 (233.4)
    This gives you moles x

    The reaction was this:

    BaCl2 + H2SO4 --> BaSO4 + 2HCl

    Meaning the number of moles of BaCl2 is also x
    Multiply x by Mr of BaCl2 (208.3) to get mass of BaCl2 (y)

    Percentage of MgCl2 therefore:

    [(1.506-y)/1.506]*100

    I am just using 1.506 randomly, I can't remember what the total mass of both MgCl2 and BaCl2 was, but the above is the method.
    And I got 35.something % from this method.
    That is correct. I had 35.4%
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    (Original post by rheajain)
    Ya! How did you find it?

    I was wtf for the mass spec question. I put for the similarity the number of peaks and for the difference I put height of the peaks. I know that's completely wrong. For the percentage yield I put 49.3% I think. And then the last question which method would give the highest atom economy, I guessed and put the first method. But I just guessed. For the cracking of an alkane to produce one molecule of octane and ethene and a compound X what did you get as the molecular formula of the alkane I just put c12h26 no clue tho.
    I thought it went okay, I messed up that similarity and differences one. Yeah I got 40 something for the perc yield one, I put method one as well. I got C14H30 for that one, I don't know which is correct. What did you put for the one where the selenium compound had a higher boiling point than the sulphur containing compound?- couldn't remember the exact question
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    (Original post by Science_help)
    Before lowering peoples hopes you should really invest some time doing actual research rather then plucking random 'facts'.

    you said the last 5-7 years grade boundries never fell below 80? lmao do some research

    Actual facts : unit 1 chem had gone below 80% for an A a few rimes before, but by much , around 77%, however we have to also take into account unit 2 chem, as our exam today was a mix of last year unit 1 and 2. And unit 2 chem has sometimes gone as low as 67% for a A .

    Therefore, with all due respect please stop putting hopes down, grade bounrdies should most definetly go down. And the issue here isn't wehter they will or not, its just a matter of false information provided to the many people reading this thread.

    Think before you speak, and don't fabricate facts.
    Savage 😂👌🏽
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    (Original post by PurpleJag)
    I thought it went okay, I messed up that similarity and differences one. Yeah I got 40 something for the perc yield one, I put method one as well. I got C14H30 for that one, I don't know which is correct. What did you put for the one where the selenium compound had a higher boiling point than the sulphur containing compound?- couldn't remember the exact question
    Well for some stupid reason I put c12H26. I put that the selenium compound one I think it was CH3SeH had more electrons so it is a bigger molecule. This means that it has a larger surface area and more points of contact. It also has more van der Waal's forces than the CH3SH compound so requires more energy to break bonds.
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    The good thing about the AS grades, is that it will not count towards the A levels however I would like to do well so that I can get into a university of my choosing.
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    (Original post by queenleelee)
    What did everyone get for the Mr of the MHCO3 compound? I got 164! Plus may someone please explain the reaction between sodium chlorate and potassium idodide! Really had no clue
    That's sounds like what I got!!
    I said that the reaction produces a black solid as I2 is produced not sure tbh
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    (Original post by rheajain)
    Well for some stupid reason I put c12H26. I put that the selenium compound one I think it was CH3SeH had more electrons so it is a bigger molecule. This means that it has a larger surface area and more points of contact. It also has more van der Waal's forces than the CH3SH compound so requires more energy to break bonds.
    You're probably correct about the cracking one, ohh that makes sense I had no idea what to put so last minute I wrote about electronegativity differences which is probably wrong now I've read what you've put
    Do you remember what you got for the ideal gas one?
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    anyone got the paper with answers on can you please attach it on with mark scheme.
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    (Original post by Asad_2015)
    Guys it was a hard exam, and I'm saying this because a lot of you are worried. Don't be, all we can do is revise for the next one now. I know it's hard to get your mind off it but i know everyone and including me have worked our socks off, we can't turn the clock back, we wish we could but we can't. What I'm saying is that it's half term now, so guys just take 2/3hrs rest, every single one of us deserves a bit of rest These exams are turning us into robotic like things :s It's always better to keeping walking forward than walking back all the way and realising, nothing is left...

    Predictions A: 55-58/80, B: 48/80, C: 39/80
    This was so nice to read! Thank you
 
 
 
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