I am supposed to give the two half reactions , then the net equation, for the following redox reaction:
H2O2 + I- ----> I2 + H2O
I had balanced these as:
2 I2 + 2 electrons ----> 2 I-
H2O2 ----> H2O + 2 electrons
For a net reaction of:
H2O2 + 2 I2 ----> H2O + 2 I-
I'm told this is wrong, but I can't see any other way to do it, and don't understand what I'm doing incorrectly. Please help!
I need help balancing these two half-reactions.
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You can't just add electrons willy nihly, you have to have justification.
In the hydrogen peroxide half equation, first balance the hydrogen with protons, and then balance the charge with electrons.
In the iodide half reaction, reverse the order.
Combine so that the electrons cancel (just as is).
In the hydrogen peroxide half equation, first balance the hydrogen with protons, and then balance the charge with electrons.
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H2O2 + 2 H{+} + 2 e{-} = 2 H2O
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2 I{-} = I2 + 2 e{-}
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H2O2 + 2 H{+} + 2 I{-} = I2 + 2 H2O