How is the oxidation state of a transition metal determined from the chemical formula ?

Explanation:

In a chemical formula, the oxidation state of transition metals can be determined by establishing the relationships between the electrons gained and that which is lost by an atom.

We know that for compounds to be formed, atoms would either lose, gain or share electrons between one another.

The oxidation state is usually expressed using the oxidation number and it is a formal charge assigned to an atom which is present in a molecule or ion.

To ascertain the oxidation state, we have to comply with some rules:

For example, let us find the oxidation state of Cr in Cr₂O₇²⁻

This would be:  2x + 7(-2) = -2

                          x = +6

We see that the oxidation number of Cr, a transition metal in the given ion is +6.

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