What is ozone?

We often hear today about the damaging ultraviolet rays, ozone and ozone holes. What is ozone, which is very dangerous and at the same time extremely necessary for all living things on planet Earth?

We often hear today about the damaging ultraviolet rays, ozone and ozone holes

In nature, ozone occurs in the stratosphere at an altitude of 15-30 km from molecular oxygen under the influence of ultraviolet rays. In the lower layers of the atmosphere, a small amount of ozone occurs after a thunderstorm, and this explains the feeling of freshness in the air. The ozone layer is very thin and if it could be compressed at ordinary atmospheric pressure, it would have a thickness of only 2-3 mm! By absorbing scorching and deadly ultraviolet rays, ozone is a reliable shield of all life on Earth. Without him, life on Earth would cease.

Some believe that in the coniferous forest, air has an increased ozone content. In fact, there is no ozone in the forest air at all, since in the presence of some organic substances that are easily oxidized by ozone, its existence there is simply impossible.

In addition to the physical methods of extraction (the action of an electric discharge in an ozonizer and ultraviolet radiation of a mercury-quartz lamp), ozone, or rather ozonized oxygen, in laboratories can also be obtained chemically, for example, by the action of cooled concentrated H2SO4 for dry BaO2 or KMnO4, (heating the mixture is dangerous):

a2 + H2SO4 = BaSO4 + H2O2, H2O2 = H2O + O 2O = O2; 3 = O3.

Ozonated oxygen with a rather high content of ozone (12,5% and more) is often produced by electrolysis of perchlorate or sulfate acids with platinum electrodes (ozonized oxygen is released at the anode). To separate pure ozone, its mixture with oxygen is liquefied with liquid air, and more volatile oxygen is then aspirated. Liquid ozone is a dark purple liquid. If it is cooled to -251,50 C, it freezes.

It is interesting that pure gaseous ozone explodes even from breathing, and liquid can explode from impact, shock, contact with combustible substances, or even simply during transfusion from one reservoir to another. Therefore, liquid ozone is used as an oxidizer in rocket engines only in the form of solutions in liquid oxygen. And although the replacement of pure ozone with its solutions, the thermal characteristics of rocket fuel are reduced, but the danger of explosion is eliminated.

Why is ozone so unstable? The reason is that ozone is an endothermic compound, since a lot of energy is spent during its formation:

32 = 23 68 cal.

Excess energy in the molecules of ozone and determines their low resistance. During the decay of ozone, this energy is released.

In the environment of ozone, the tensile rubber tears. This is due to the fact that rubber molecules are easily oxidized by ozone and are destroyed, so that rubber loses its elasticity and elasticity.

In addition, ozone destroys and red blood cells. This dangerous gas causes hereditary changes (mutations) in the human genes, which can lead to the fact that children can be born cripples. The latest studies have established that even such a small concentration of ozone in the air, as 0,00001% by volume, for 10 minutes acts on the human body as destructive as 250 X-rays of radiation. Therefore, in research laboratories and in engineering with this gas, one must behave extremely cautiously, observing all the safety rules.