3(lost 2 electrons)
                              ______________________
                              |                                           |
                                                            1(-1)                                                                               1(+1)
3H+ + 2HClO2 + 3I- → Cl2 + 3HIO + H2O
2(+3)                                                                              2(0)                                           
|_____________________|                      

gain 6 electrons                    

 

  1st:    Balance all atoms with the exception of Hydrogen and Oxygen.

 

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