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    Confused on ques 2.c)
    So i worked out thre units to be mol-1dm3 which is wrong. You have one product at the top and 2 reactants at the bottom so you gwt 1 over moldm-3 which i reversed to get mol-1dm3

    For part c i got 0.036^2 divided by [SO2]^2 × 0.18 = 15
    Rearranging i got sq root of 0.18 x 15 al divided by 0.036^2 which is wrong. In the answer they have the fraction reversed. Help please Attachment 505551505557
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    (Original post by kiiten)
    Confused on ques 2.c)
    So i worked out thre units to be mol-1dm3 which is wrong. You have one product at the top and 2 reactants at the bottom so you gwt 1 over moldm-3 which i reversed to get mol-1dm3

    For part c i got 0.036^2 divided by [SO2]^2 × 0.18 = 15
    Rearranging i got sq root of 0.18 x 15 al divided by 0.036^2 which is wrong. In the answer they have the fraction reversed. Help please Attachment 505551505557
    I thought Kc was constant regardless of concentration of products or reactants as the position of equilibrium shifts to counteract any change in concentration? I'll give you a free bump as i'm equally as puzzled.
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    (Original post by BioStudentx)
    I thought Kc was constant regardless of concentration of products or reactants as the position of equilibrium shifts to counteract any change in concentration? I'll give you a free bump as i'm equally as puzzled.
    Kw is always constant, Kc doesnt have to be
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    (Original post by samb1234)
    Kw is always constant, Kc doesnt have to be
    Whats kw
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    (Original post by kiiten)
    Whats kw
    Ionic product of water, basically its the equilibrium constant for 2 H2O <-> h3o+ + oh-
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    (Original post by samb1234)
    Ionic product of water, basically its the equilibrium constant for 2 H2O <-> h3o+ + oh-
    I thought Kc only changed with temperature. Changes in concentration doesn't affect it. At least that's what my A level ocr text book states.
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    (Original post by BioStudentx)
    I thought Kc only changed with temperature. Changes in concentration doesn't affect it. At least that's what my A level ocr text book states.
    Sorry yeah i misread what you wrote. It doesnt make a difference to the question, its just a hypothetical question to get you to manipulate the kc equation ther way around, probably because they are lazy and couldnt be bothered to write a whole new question with the Kc is ... Work out conc of x
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    Kw changes with temp.

    Soz.
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    looking for unknown SO2 concentration so rearrange equation to get [SO2]2= [SO3]2 / Kc x [O2]

    sub in known values [SO2]2 = [0.36]2 / 15 x [0.18]
    [SO2]2 = 0.048
    [SO2]= 0.219 or 0.22
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    (Original post by GO97)
    looking for unknown SO2 concentration so rearrange equation to get [SO2]2= [SO3]2 / Kc x [O2]

    sub in known values [SO2]2 = [0.36]2 / 15 x [0.18]
    [SO2]2 = 0.048
    [SO2]= 0.219 or 0.22
    Thanks

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    (Original post by GO97)
    looking for unknown SO2 concentration so rearrange equation to get [SO2]2= [SO3]2 / Kc x [O2]

    sub in known values [SO2]2 = [0.36]2 / 15 x [0.18]
    [SO2]2 = 0.048
    [SO2]= 0.219 or 0.22
    What about the units i got 1/moldm-3 which is mol-1dm3 but in the book it says moldm-3 ???

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    (Original post by kiiten)
    What about the units i got 1/moldm-3 which is mol-1dm3 but in the book it says moldm-3 ???

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    could be a mistake in the answer scheme, is the answer i got to correct? if so then 1/moldm-3 or mol-1dm3 is definetly right.
 
 
 
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