Question

What is the oxidation number of s in Na2S4O6

Answer 1

Na2S4O6

Out of the four S atoms, S2 and S3 are bonded with S atoms and this their oxidation state is 0.

The atoms S1 and S4 are bonded with O atoms which result in oxidation state of +5 on S1 and S4.

Many people write the average oxidation that is (5+0+0+5)/4 = 2.5


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