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    Hi,
    I am a bit confused about how to approach this question as the mark scheme uses methods which I do know. However, am unsure what to do with the "maximum solubility" and how to approach it.

    Thanks
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    (Original post by chrlhyms)
    Hi,
    I am a bit confused about how to approach this question as the mark scheme uses methods which I do know. However, am unsure what to do with the "maximum solubility" and how to approach it.

    Thanks
    "the most that will dissolve"

    This is basically a units convertion question.

    "What is x mol dm-3 expressed in ppm?"
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    (Original post by charco)
    "the most that will dissolve"

    This is basically a units convertion question.

    "What is x mol dm-3 expressed in ppm?"
    I see, do I not need to use the density at all?
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    (Original post by chrlhyms)
    I see, do I not need to use the density at all?
    You need the density to calculate the mass of 1 litre of solution.
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    (Original post by charco)
    You need the density to calculate the mass of 1 litre of solution.
    How would I do that?
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    (Original post by chrlhyms)
    How would I do that?
    density is mass per unit volume
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    (Original post by charco)
    density is mass per unit volume
    I'm still confused, so is this right:

    You want the value in grams and 1x10^-6 =1ppm,
    so 2.8x10^-4 x 32 (Mr of O2) = 8.96x10^-3g/dm^3

    and as 1dm^3=1000g
    8.96x10^-3/1000 = 9x10^-6g therefore = 9ppm?

    Is this method correct? As the answer is 9
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