Properties of Ozone

Ozone (O3) is the triatomic, allotropic form of oxygen (O2). It is an unstable gas with a pungent odor. Since ozone is unstable, it must be generated at the point of application. The Ozone molecule, having a molecular weight of 48, is made up of three oxygen atoms bound by equal oxygen-oxygen bonds at an obtuse angle of 116o49. This structure is inherently unstable and is the reason for ozones powerful oxidizing ability. Ozone has approximately 150% the oxidizing potential of chlorine. The physical properties of ozone and comparative oxidizing potentials for other chemical oxidants are presented in Table 1 and Table 2, respectively.
Table 1Physical Constants of Ozone Table 2Comparative Oxidizing Potentials,25oC Volts
Molecular weight, g/g-mol
48.0 Fluorine (F2)
2.87
Boiling point, oC
-111.9 Ozone (O3)
2.07
Melting point, oC
-193 Hydrogen Peroxide (H2O2)
1.78
Gas density, 0oC grams/liter
2.144 Potassium Permanganate (KMnO4)
1.70
Critical temperature, oC
-12.1 Hyprobromous Acid (HOBr)
1.59
Critical pressure, atm.
54.6 Hypochlorous Acid (HOCl)
1.49
Critical volume, cc/mol
147.1 Chlorine (Cl2)
1.36 Chlorine dioxide (ClO2)
1.27 Oxygen (O2)
1.23 Chromic Acid (H2CrO4)
1.21 Bromine (Br2)
1.09 Nitric Acid (HNO3)
0.94 Iodine (I2)
0.54