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Kinetics A2. I AM IN URGENT NEED OF HELP! I HAVE BROKEN TWO BIRO PENS IN ANGER! watch

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    I've been trying question 1.a) for one hour and a half...ONE HOUR AND A HALF AND ITS ONLY WORTH 3 ******* MARKS :emo: I'm so upset that i can't do this I'm about to cry. I don't know why I can't get it. How can you do a 3 mark question for more than an hour? Am I that stupid, really? :sigh:

    I found the order with respect to [B] = 1. I can't find [A] or [C]. My teacher taught us to add an extra row. please can someone help me/teach me? i'm not the brightest bulb in the box. please can anyone explain how to do this? I will do anything for help. Does anyone know about this extra row?
    PLEASE HELP A STUPID PERSON!


    i know my rep is worth nothing, but i will repay anyone who helps me with this question!
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    I remember this question, everytime I tried it I got 0 order for B but it was wrong on the mark scheme, move on, I'm pretty sure it's a defective question and you'll get the others right
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    What does the MS say the answers are?
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    Are you sure??? AQA have done this several times with other questions. But what if it isn't a defective question? What if I just can't do it? Imagine if I came across this in an exam...I would have just lost 3 easy marks
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    (Original post by LearningMath)
    What does the MS say the answers are?
    A is 2
    B is 1
    C is 0

    any ideas on how to do this?
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    (Original post by h-star)
    I remember this question, everytime I tried it I got 0 order for B but it was wrong on the mark scheme, move on, I'm pretty sure it's a defective question and you'll get the others right
    B isnt zero order.
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    (Original post by Mathematics.)
    A is 2
    B is 1
    C is 0

    any ideas on how to do this?
    i got A=2
    b=1
    working on c
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    (Original post by Mathematics.)
    A is 2
    B is 1
    C is 0

    any ideas on how to do this?
    Excellent same as mine, was slightly apprehensive about giving you wrong answers though. Solid question! :p: I'll just write up my method....
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    (Original post by PsYCho ThInKeR)
    i got A=2
    b=1
    working on c
    can you help me?
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    (Original post by LearningMath)
    Excellent same as mine, was slightly apprehensive about giving you wrong answers though. Solid question! :p: I'll just write up my method....
    you got it so quickly? oh dear. i am dumb then. i'm on the verge of throwing myself off a bridge.
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    (Original post by Mathematics.)
    A is 2
    B is 1
    C is 0

    any ideas on how to do this?
    lol I actually found these answers without pen/paper. It's not even part of my curriculum (also at A2 level, though). :awesome:

    I'll tell you how I found them, just a sec..!
    edit: nvm, someone else (LearningMath) is doing the same. :P

    edit: it just struck me that this is a past paper and it's this easy.. A levels must be a cakewalk. no offence meant..
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    (Original post by LearningMath)
    B isnt zero order.
    :sigh: Oh well.
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    (Original post by Mathematics.)
    can you help me?
    for A
    look at row 2 and 3.
    b goes 0.8 to 0.4. so it halves. the rate should also half making it 0.8. (b has an order of 1)
    A doubles.
    and the value is 3.2 x 10
    3.2 divide by 0.8 = 4
    A doubles and rate is times by 4
    hence rate is 2. (2:4)
    im not very good at explaining. hope u understand
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    (Original post by phen)
    lol I actually found these answers without pen/paper. It's not even part of my curriculum (also at A2 level, though). :awesome:

    I'll tell you how I found them, just a sec..!
    edit: nvm, someone else (LearningMath) is doing the same. :P

    edit: it just struck me that this is a past paper and it's this easy.. A levels must be a cakewalk. no offence meant..
    that really didn't help. thanks for ********. :emo:
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    First find B since it is the simplist one. Look at rows 1 and 2, concs of A and C are constant and B is doubled twice, the rate also doubles twice. So 1st order.

    To find A look at rows 2 and 3, since C is constant and you know the order of B. From row 2 to 3 you are doubling A and halving B. The rate is doubling from 1.6 to 3.2. The only way this could happen was if A was 2nd order, because the rate would quadruple from increase of A(to 6.4x10^-3) and then halve to 3.2x10^-3 as a result of B.

    For C, look at rows 3 and 4 since A is constant. The ratio of concentrations of B is exactly the same as the ratios of rates. (0.8/0.3=2.66) and (1.6/0.6=2.6666) which means first order. We know B is first order, so by process of elimination C must be zero order.
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    (Original post by Mathematics.)
    that really didn't help. thanks for ********. :emo:
    I was going to help but you're already being helped, so.. no point in doing so, really.

    edit:

    I've had your situation at tests (well.. an olympiad) too.. I was completely raped by a complete and utter overdose of material I hadn't at all covered. In the end, I got 36 out of 111 points.. 3 short of making it to the next round. *sigh*
    Better luck this year.

    Sorry for being a bit inconsiderate.
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    Honestly, I have no idea what its talking about (Being an English student :p:) but I felt the need to tell you OP that if I had not already used my rep like 2 minutes ago I would have repped you for the title of this thread :p:
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    LearningMath has explained it better.
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    (Original post by PsYCho ThInKeR)
    for A
    look at row 2 and 3.
    b goes 0.8 to 0.4. so it halves. the rate should also half making it 0.8. (b has an order of 1)
    A doubles.
    and the value is 3.2 x 10
    3.2 divide by 0.8 = 4
    A doubles and rate is times by 4
    hence rate is 2. (2:4)
    im not very good at explaining. hope u understand
    did you use an extra row? i dont understand.
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    (Original post by LearningMath)
    First find B since it is the simplist one. Look at rows 1 and 2, concs of A and C are constant and B is doubled twice, the rate also doubles twice. So 1st order.

    To find A look at rows 2 and 3, since C is constant and you know the order of B. From row 2 to 3 you are doubling A and halving B. The rate is doubling from 1.6 to 3.2. The only way this could happen was if A was 2nd order, because the rate would quadruple from increase of A(to 6.4x10^-3) and then halve to 3.2x10^-3 as a result of B.

    For C, look at rows 3 and 4 since A is constant. The ratio of concentrations of B is exactly the same as the ratios of rates. (0.8/0.3=2.66) and (1.6/0.6=2.6666) which means first order. We know B is first order, so by process of elimination C must be zero order.
    but from row 2 to 3 aren't you halving a and doubling b?
 
 
 
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