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    Haven't really seen a question like this before :

    The solubility of carbon dioxide, Mr 44, in water at 25 °C and atmospheric pressure is
    0.145g/100g H2O.

    Calculate its concentration in mol dm–3.

    -----------

    I started off trying to use the formula c = m/v

    The moles would be mass/mr so 0.145/44 . I then done 0.145 over this total and end up with 2.2 .

    Don't really know how to do it , also how do i convert gdm3 to mol dm3
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    (Original post by Tulian)
    Haven't really seen a question like this before :

    The solubility of carbon dioxide, Mr 44, in water at 25 °C and atmospheric pressure is
    0.145g/100g H2O.

    Calculate its concentration in mol dm–3.

    -----------

    I started off trying to use the formula c = m/v

    The moles would be mass/mr so 0.145/44 . I then done 0.145 over this total and end up with 2.2 .

    Don't really know how to do it , also how do i convert gdm3 to mol dm3
    It's easier than you think. You are going about it correctly.

    Moles of CO2 = 0.145/44

    This in 100g water (equals 100ml)

    So moles per litre = 10 * 0.145/44
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    (Original post by charco)
    It's easier than you think. You are going about it correctly.

    Moles of CO2 = 0.145/44

    This in 100g water (equals 100ml)

    So moles per litre = 10 * 0.145/44

    Thanks

    Okay I got the moles part, just not sure why you got the litres part and x it by 10 ? Why is 100ml needed ?
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    (Original post by Tulian)
    Thanks

    Okay I got the moles part, just not sure why you got the litres part and x it by 10 ? Why is 100ml needed ?
    ... because you are told how much dissolves in 100g = 100ml

    ... and you need moles per litre = 1000ml

    Ten times as much.
 
 
 
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