The key difference between oxygen and ozone is that the oxygen is a diatomic gaseous molecule of oxygen element, whereas ozone is a triatomic molecule of oxygen.
Oxygen gas and ozone are the most familiar allotropes of oxygen element. Oxygen is an extremely important gas for living organisms; for their respiration. Ozone also protects life on earth when it is in the upper atmosphere, but at the lower atmosphere, it is harmful.
What is Oxygen?
Oxygen is a chemical element with atomic number 8, which is present in group 16 of the periodic table. It has the electron configuration 1s2 2s2 2p4. Oxygen has three major isotopes; 16O, 17O, 18O. Among these, 16O is the most abundant isotope. Moreover, the oxygen atom has eight electrons, and it can obtain two more electrons from another atom to form a -2 charged anion. Alternatively, two oxygen atoms can share four electrons to form covalent bonding which gives the diatomic molecule (O2).
The molecular weight of O2 is 32 g mol-1. It is a colourless, odourless, tasteless gas. There is about 21% of oxygen in the earth atmosphere. Further, it is poorly soluble in water and is slightly heavier than air. Oxygen has magnetic properties too. When oxygen gas condenses at -183°C, it becomes a bluish colour liquid.
Also, this gas reacts with all the elements to form oxides except inert gases. Therefore, it is a good oxidizing agent. Oxygen is essential in respiration of living organisms. We use this gas in hospitals, welding, and in many other industries.
What is Ozone?
The three-atomic form of oxygen is ozone, and it is a common form of oxygen. As soon as we hear the name ozone, we think of the ozone layer. The ozone layer is present in the stratosphere at the higher atmospheric level, and it absorbs harmful UV radiation, thus restricting it from getting to the earth surface.
However, ozone is harmful at lower atmospheric levels. It acts as an air pollutant (responsible for photochemical smog) and can cause respiratory diseases to humans and animals. Furthermore, it damages the plants too. Ozone is less stable than oxygen gas, hence; break into more stable oxygen gas.
The ozone gas is a pale blue colour gas with a sharp odour. It is more soluble in non-polar solvents and less soluble in water. Moreover, two oxygen atoms in the ozone bind together with a double bond, and there is a dative bond between one oxygen atom with another oxygen atom.
However, it shows resonance stabilization; thus, the actual structure of this molecule is a hybrid structure. There, the O-O bond length is similar between three atoms. The central oxygen atom has sp2 hybridization with one lone pair. Moreover, the ozone has bent geometry. Also, it is a polar molecule. And, since it is a strong oxidizing agent, ozone is highly reactive. Besides, this gas forms from the oxygen when there is sunlight.
What is the Difference Between Oxygen and Ozone?
Oxygen is a chemical element with the atomic number 8 and symbol O and ozone is a gaseous compound with chemical formula O3. Generally, when we say oxygen, we refer to the oxygen gas. Hence, the key difference between oxygen and ozone is that the oxygen gas is a diatomic gaseous molecule of oxygen element, whereas the ozone is a triatomic gaseous molecule of oxygen. Moreover, there is a difference between oxygen and ozone in their colors as well. That is; the oxygen is a colourless gas, but ozone is a pale blue gas.
Furthermore, another significant difference between oxygen and ozone is that the ozone gas can be harmful at lower atmospheric levels but, oxygen is not a harmful gas. Besides, in the atmosphere, oxygen gas occurs in much higher quantities than ozone. Apart from that, ozone is less stable than oxygen. Therefore, the oxidation ability of ozone is higher than that of oxygen.
The below infographic on the difference between oxygen and ozone shows the differences in tabular form.
Summary – Oxygen vs Ozone
Oxygen and ozone are the two major gaseous compounds of the chemical element oxygen. The key difference between oxygen and ozone is that the oxygen is a diatomic gaseous molecule of oxygen element, whereas the ozone is a triatomic molecule of oxygen.
1. “Ozone.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine. Available here
2. “Oxygen.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine. Available here