At stp o2 and o3 have different properties because o3 has

At STP O2 and O3 have different properties because O3 has different molecular structure (formula) than O2.

O3 is a triatomic molecule, i.e it has three atoms.

O2 is a diatomic molecule, i.e. it has two atoms.

So, they two have different physical and chemical properties.

For example, O2 is odorless while O3 has a strong characteristic odour.

From the chemical point of view, O3 is very unstable and more reactive than O2.