The balanced chemical equation for the reaction between oxygen (O₂) and iron (Fe) to form iron(III) oxide (Fe₂O₃) is:

4 Fe + 3 O₂ → 2 Fe₂O₃

Here's how to balance the equation:

1. Identify the reactants and products:

- Reactants: Fe and O₂

- Product: Fe₂O₃

2. Count the number of atoms of each element on both sides of the equation:

| Element | Reactants | Products |

|---|---|---|

| Fe | 1 | 2 |

| O | 2 | 3 |

3. Balance the equation by adjusting the coefficients in front of each chemical formula:

- To balance the iron atoms, add a coefficient of 4 in front of Fe on the reactants side.

- To balance the oxygen atoms, add a coefficient of 3 in front of O₂ on the reactants side and a coefficient of 2 in front of Fe₂O₃ on the products side.

4. Verify that the equation is balanced:

| Element | Reactants | Products |

|---|---|---|

| Fe | 4 | 4 |

| O | 6 | 6 |

Now the equation is balanced with 4 iron atoms and 6 oxygen atoms on both sides.