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    Could someone help me work through question 2 b (i) here:

    http://store.aqa.org.uk/qual/gceasa/...W-QP-JUN07.PDF

    Have not really seen this type of question.

    Cheers.
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    (Original post by alevelsguy)
    Could someone help me work through question 2 b (i) here:

    http://store.aqa.org.uk/qual/gceasa/...W-QP-JUN07.PDF

    Have not really seen this type of question.

    Cheers.
    protip: sodium carbonate (edit: i.e. the carbonate thingy can act as a base twice.. so to say)
    kind of a give-away, I'd say..
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    (Original post by alevelsguy)
    Could someone help me work through question 2 b (i) here:

    http://store.aqa.org.uk/qual/gceasa/...W-QP-JUN07.PDF

    Have not really seen this type of question.

    Cheers.
    Carbonate ions can react with acids stepwise...
    acids react by using their hydrogen ions:

    H+ + CO32- --> HCO3-

    H+ + HCO3- --> CO2 + H2 O

    This is why there are two points of inflexion and why bubbles of gas are only seen arfter the second of the two inflexions
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    nice! i got that thanks a lot. just one thing, why does the carbonate have a 2- charge in the first step?
 
 
 
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