Question

How do you find oxidation numbers of elements?

Answer 1

Normally an element is zerovalent; that is it has an oxidation number of `0`.

Explanation:

When we assign oxidation numbers to atoms in molecules we formally separate charges and electrons. An element is conceived to have a `0` oxidation state, in that electron transfer has not taken place.

For instance in the simple combustion rxn:

`C + O_2 rarr CO_2`

The carbon is the reductant, and transfers electron to the oxidant; clearly a redox process is exemplified.