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Redox question

I'm trying to revise how to write equations for oxidation and reduction reactions but everytime I search for them it only gives me half equations? I know ehat they are but how am I supposed to write a full oxidation/reduction equation with them? would I have to do each half equation then combine them?
Original post by fzmannan
I'm trying to revise how to write equations for oxidation and reduction reactions but everytime I search for them it only gives me half equations? I know ehat they are but how am I supposed to write a full oxidation/reduction equation with them? would I have to do each half equation then combine them?


The full equations show the actual species involved in the reaction and the spectator (balancing) ions.

The balancing ions really do not matter. However, if you wish to generate a "full" equation, you only have to add the ions that go with the reacting species.

For example, in the reaction between iodine and sodium thiosulfate:

2S2O32- + I2 ==> S4O62- + 2I-

The ionic equation shows only the reacting species and ignores the sodium ions. But if you wish to include sodium, then for every thiosulfate you need two sodium ions:

2Na2S2O3 + I2 ==> Na2S4O6 + 2NaI

Don't forget that ionic compounds in solution are dissociated 100%, so the sodium ions are just floating around in the solution both before and after the redox reaction. They are mere spectators to the reaction.
Reply 3
thank you!

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