The term "empirical formula" refers to the simplest whole-number ratio of atoms in a compound. In the case of hydrogen peroxide:

* There are two hydrogen atoms (H) for every two oxygen atoms (O).

* The simplest ratio for this is 1:1.

However, the molecular formula of hydrogen peroxide is also H₂O₂. This means that the actual number of atoms in a molecule of hydrogen peroxide is two hydrogen atoms and two oxygen atoms.

So, why the confusion?

Sometimes, the terms "empirical formula" and "molecular formula" get mixed up. They are distinct, though related:

* Empirical Formula: The simplest ratio of atoms in a compound.

* Molecular Formula: The actual number of atoms of each element in a molecule.

In the case of hydrogen peroxide, the empirical and molecular formulas are the same. This isn't always the case – many compounds have different empirical and molecular formulas.