Ozone: Ozone Layer Depletion, Formation of Ozone, Properties of Ozone, Uses and Ozonizer

Ozone layer depletion is one of the negative consepuences of modern man interaction with his immediate environment. The ozone layer is popularlly referred to as the Blanket of the Earth by virtue of its ability to absorb large amount and shield man of harmful uv-radiation from the Sun. uv-ray are electromagnetive radiations that are capable of changing the structure and function of living systems in a way that could hamper the productiveness of plants and animals. and by extension, the ecosystem. Livestocks for instance, could go blind, while certain parts of plants could be deformed in a way that could affect food production and the ecosystem..

Ozone Layer depletion starts from the decomposition of the Ozone Molecule. Here, the unstable ozone molecule absorbs uv-ray, gets excited, and decompose into molecular oxygen and atomic oxygen.

O₃(g) → O₂(g) + O(g)

Although there is a reverse process of formation of ozone molecule from both molecular oxygen and atomic oxygen, this reaction becomes complex by the presence of some chemicals called fluorochloro Carbon. They create environment that shift the stability of the reaction to the rapid splitting of the ozone molecule than the formation of new ones.

Ozone is found abundantly in the stratosphere. But what is uncommon is the reality that it is actually formed in our immediate vicinity. For example, it is formed from electric sparks in vehicle engines and in electrical appliances like in photocopying machines where the users are unconscious of it formation. But it is the deliberate formation from the passage of streams of oxygen through an electric discharge tube, and the reaction of nitrogen oxides with hydrocarbons in the presence of sunlight that are essential for tangible isolation.

But there is a more important ozone formation process. That is the formation of ozone in the Earth's Stratosphere ( ie 20 to 50 Km above the Earth's surface) from Oxygen. UV-ray plays a constructive role in this case, rather than the destructive role. Here, the uv-ray is absorbed by molecular Oxygen gas which eventually decompose to Atomic Oxygen gas.

O₂(g) → O(g) + O(g)

Each atomic oxygen gas then migrate to attack molecular oxygen in the presence of electric charge generated from lightening to form ozone molecule. This is represented in an equation of reaction as,

O₂(g) + O(g) → O₃(g) + M(g)

Here, M is the carrier of excess energy.

The smell of ozone is like chlorine with characteristic pungent smell. It is pale-blue in colour and also exist in liquid state as pale-blue liquid at -112°C and slightly soluble in water. Ozone is also a poisonous gas at concentration of hundred ppm, but harmless at lower concentration. .

Ozone shares some similar chemical properties with Oxygen. But it is more reactive than oxygen so that it is a more powerful oxidising agent used as a bleaching agent. Ozone has also found use in ventillation where it is used to ventilate places with limited supply of oxygen. Ozone is also used as disinfectant in water purification plants and to purify sewages.The equation of the strong oxidising property of ozone can be expressed as,

SO₂(g) + O₃(g) → SO₃(g) + O₂(g)

One other important feature of ozone is the impact of heat on the molecule. The triatomic molecule of ozone is highly unstable, as such can easily dissociate to molecular oxygen. This is an essential precaution for the handling of ozone. The equation of reaction of the decomposition can be expressed as,

2O₃(g) → 3O₂(g)

Ozone is commonly prepared by the use of an Ozonizer device. Dry oxygen is passed through one end of the ozonizer into the chamber where the inner electric discharge system ionizes the oxygen to ozone. The ozonizer is made up of concentric glass tubes with two induction coils connected to tin foil the electric discharge system made possible by a connection of two Induction Coils to Tin foil.