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Homework Help: Question regarding buffer

  1. Sep 19, 2006 #1
    Here's the buffer solution H2O + CO2 <=> HCO3- + H+ so the question is why when OH- is added to the solution it reacts with CO2 to get HCO3- and H+ :confused: how do you know which one will OH- react with?Why doesnt the OH- react with the H+ :confused:
     
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  3. Sep 19, 2006 #2

    Borek

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    Staff: Mentor

    Are you telling that reaction that takes place is

    CO2 + OH- <-> HCO3- + H+

    It can't be balanced (which usually means that such reaction doesn't take place).
     
  4. Sep 19, 2006 #3
    So what happen when OH- is added to the buffer?
     
  5. Sep 19, 2006 #4

    GCT

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    It should react with the predominant acid in the solution.
     
  6. Sep 20, 2006 #5
    ermz...so how do you know which one is the acid?I mean in cases where the acid and base is not so obvious?
     
  7. Sep 20, 2006 #6

    Borek

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    Staff: Mentor

    In general you may safely assume that OH- always reacts with H+. That in turn may move equilibrium of other reactions (acid/base dissociations) according to the LeChatelier's principle.
     
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