The formulas H2O2 and H2O do not represent the same compound. H2O2 is the formula for hydrogen peroxide, while H2O is the formula for water. Hydrogen peroxide is a molecule that contains two hydrogen atoms and two oxygen atoms, while water is a molecule that contains two hydrogen atoms and one oxygen atom. Hydrogen peroxide is a strong oxidizing agent and is used in many different industrial and consumer applications, while water is essential for life and is the most abundant compound on the surface of the Earth.