The atomicity of ozone is 3.
Atomicity refers to the number of atoms present in a molecule of a substance. For example, in oxygen gas (O2), the atomicity is 2 because there are 2 oxygen atoms in a molecule of O2.
Ozone (O3) is a molecule made up of 3 oxygen atoms. This means that the atomicity of ozone is 3, because there are 3 atoms in each molecule of ozone.
It's important to note that atomicity is different from the chemical formula of a substance. The chemical formula of ozone is O3, which tells us that there are 3 oxygen atoms present in a molecule of ozone. But the atomicity specifically refers to the number of atoms in a single molecule of a substance.