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    If the concentration of a reagent is 0.0400 mol dm-3 and 1cm3 of water is being added to it... Does it mean that the new concentration of the reagent is 0.039 mol dm-3? By 0.400 mol dm-3 - 0.001dm3
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    (Original post by MacOne)
    If the concentration of a reagent is 0.0400 mol dm-3 and 1cm3 of water is being added to it... Does it mean that the new concentration of the reagent is 0.039 mol dm-3? By 0.400 mol dm-3 - 0.001dm3
    It all depends on the volume of your reagent used ...

    Calculate the moles of reagent by concentration x volume in litres.

    After the addition of water

    Divide the moles of reagent by the new volume in litres ...
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    (Original post by charco)
    It all depends on the volume of your reagent used ...

    Calculate the moles of reagent by concentration x volume in litres.

    After the addition of water

    Divide the moles of reagent by the new volume in litres ...
    Thanks for the reply.

    Conc of reagent - 0.0400 mol dm-3
    Vol reagent - 5cm3 (0.005L)

    0.0400 x 0.005L = 0.0002M

    0.0002M/ 0.004L (addition of 1cm3 of water) = 0.05 mol dm-3 (new conc)

    This is what I don't understand... Wouldn't I expect to see a decrease in its concentration?
 
 
 
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