Here's why:

* Combination Reaction: A reaction where two or more reactants combine to form a single product.

In this case:

* Reactants: Zinc (Zn) and Oxygen (O₂)

* Product: Zinc Oxide (ZnO)

The chemical equation for the reaction is:

2Zn(s) + O₂(g) → 2ZnO(s)

This equation shows that two atoms of zinc combine with one molecule of oxygen to form two molecules of zinc oxide.