1. Know the oxidation state of oxygen:

* Oxygen typically has an oxidation state of -2.

2. Determine the overall charge:

* Pb₃O₄ is a neutral compound, meaning it has a net charge of 0.

3. Set up an equation:

Let 'x' represent the oxidation state of Pb.

* 3x + 4(-2) = 0

* 3x - 8 = 0

4. Solve for x:

* 3x = 8

* x = 8/3

5. Simplify the result:

The oxidation state of Pb in Pb₃O₄ is +8/3.

Important Note: The oxidation state of Pb in Pb₃O₄ is a fraction because it represents the average oxidation state of the lead atoms in the compound. Pb₃O₄ is actually a mixed-valence compound, meaning it contains lead atoms in two different oxidation states: +2 and +4.