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Half equation problems

  1. Dec 8, 2006 #1
    I find it really hard to write half equations from the given redox reaction. I'm ok when H+ and water are not involved but when they are I get stuck.

    Eg. for this reaction:

    IO3- + 5I- + 6H+ ----------> 3I2 + 3H2O

    How would you go about splitting it up as I features as a reactant twice?
  2. jcsd
  3. Dec 8, 2006 #2
    u could try these steps-
    separate oxidation n reduction 1/2 reactions
    balance atms other than Oxygen n water
    balance H in acidic med. by adding H+ n in basic med. by adding equal no of water molecules,(ie 2H --> 2H2O) n equal no of OH- to the other side
    balance charges by adding electrons
    Add the two balanced reactions in such a way that the electrons are eliminated frm the reaction.

    For splitting Find oxidation no of all the I containing species. oxidation takes place if it inc frm rectant to product side otherwise its reduction
    Last edited: Dec 8, 2006
  4. Dec 13, 2006 #3


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    Staff: Mentor

    Start with

    IO3- -> 1/2 I2

    I- -> 1/2 I2

    Whatever will be in excess, will finally cancel out, or you will end with coefficients to simplify - both cases easy to deal with.
    Last edited by a moderator: Aug 13, 2013
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