Question

What is the oxidation number of sulfur?

Answer 1

The oxidation number of any element in its elemental state is `0`.

Explanation:

So sulfur is zerovalent, just at oxygen is as the `O_2` molecule or in its atomic state. Because sulfur is in `Group` `VI`, it has very similar redox behaviour to oxygen (or rather because oxygen and sulfur have similar chemistry, we, as chemists, put it in Group VI). Sulfur can have many oxidation states; its maximum number is `VI^+`, for example in sulfuric acid or in `SO_3`.