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    The general equation is:
    HA + OH- -----> A- + H2O

    But what about when there is 2OH- e.g. Ba(OH)2
    Is it:
    2HA + 2OH- -----> 2A- + 2H2O

    But when i use this to work out pH for a weak acid and strong base it doesnt work.

    E.g. Find pH when 50cm3 0.5moldm-3 chloroethanoic acid is added to 25cm3 0.1moldm-3 Ba(OH)2

    https://drive.google.com/open?id=0Bx...zBBdlpBY25SMGs

    If you multiply A- and HA by 2 the answer is wrong
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    You just use the general equation, but note that every mol of Ba(OH)2 produces 2 mol of OH-.
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    (Original post by Pigster)
    You just use the general equation, but note that every mol of Ba(OH)2 produces 2 mol of OH-.
    Like this?:
    HA + 2OH- -----> A- + H2O

    But that doesnt balance
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    (Original post by kiiten)
    Like this?:
    HA + 2OH- -----> A- + H2O

    But that doesnt balance
    Nope.

    Imagine adding 1 mol of Ba(OH)2 (containing 2 mol of OH-) to 10 mol of HA (able to form 10 mol of H+).

    8 mol of HA would remain and 2 mol of A- would form.
 
 
 
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