Ozone is a gas that has extremely valuable properties for all mankind. The chemical element with which it is formed is oxygen O. In fact, ozone O3 is one of the allotropic modifications of oxygen, consisting of three formula units (O÷O÷O). The first and more well-known compound is oxygen itself, more precisely the gas that is formed by two of its atoms (O=O) - O2.
Allotropy is the ability of one chemical element to form a number of simple compounds with different properties. Thanks to it, humanity has studied and uses such substances as diamond and graphite, monoclinic and rhombic sulfur, oxygen and ozone. A chemical element that has this ability is not necessarily limited to only two modifications, some have more.
History of connection opening
The constituent unit of many organic and mineral substances, including such as ozone - a chemical element, designationwhich O is oxygen, translated from Greek "oxys" - sour, and "gignomai" - to give birth.
For the first time, a new allotropic modification of oxygen during experiments with electrical discharges was discovered in 1785 by the Dutchman Martin van Marun, his attention was attracted by a specific smell. And a century later, the Frenchman Schönbein noted the presence of the same after a thunderstorm, resulting in the gas being called "smelling". But scientists were somewhat deceived, believing that their sense of smell smelled ozone itself. The smell they smelled was that of organic compounds oxidized by reacting with O3 as the gas is highly reactive.
Electronic structure
O2 and O3, a chemical element, have the same structural fragment. Ozone has a more complex structure. In oxygen, everything is simple - two oxygen atoms are connected by a double bond, consisting of ϭ- and π-components, according to the valency of the element. O3 has several resonant structures.
A double bond connects two oxygens, and the third one has a single one. Thus, due to the migration of the π-component, in the overall picture, three atoms have a one-and-a-half connection. This bond is shorter than a single bond but longer than a double bond. The experiments carried out by scientists exclude the possibility of a cyclic molecule.
Synthesis methods
For the formation of a gas such as ozone, the chemical element oxygen must be in a gaseous medium in the form of individual atoms. Such conditions are created by the collisionoxygen molecules O2 with electrons during electrical discharges or other particles with high energy, as well as when it is irradiated with ultraviolet.
The lion's share of the total amount of ozone in the natural atmosphere is formed by a photochemical method. Man prefers to use other methods in chemical activity, such as, for example, electrolytic synthesis. It consists in the fact that platinum electrodes are placed in an aqueous electrolyte environment and a current is started. Reaction scheme:
N2O + O2 → O3 + N 2 + e-
Physical properties
Oxygen (O) is a constituent unit of such a substance as ozone - a chemical element, the formula of which, as well as the relative molar mass, are indicated in the periodic table. Forming O3, oxygen acquires properties that are fundamentally different from the properties of O2.
The blue gas is the normal state of a compound such as ozone. The chemical element, formula, quantitative characteristics - all this was determined during the identification and study of this substance. The boiling point for it is -111.9 ° C, the liquefied state has a dark purple color, with a further decrease in the degree to -197.2 ° C, melting begins. In a solid state of aggregation, ozone acquires a black color with a violet tint. Its solubility is ten times higher than this property of oxygen O2. At the smallest concentrations in the air, one feelsthe smell of ozone, it is sharp, specific and resembles the smell of metal.
Chemical properties
Very active, from a reactionary point of view, is ozone gas. The chemical element that forms it is oxygen. The characteristics that determine the behavior of ozone in interaction with other substances are the high oxidizing ability and the instability of the gas itself. At elevated temperatures, it decomposes at an unprecedented rate, the process is accelerated by catalysts such as metal oxides, chlorine, nitrogen dioxide, and others. The properties of an oxidizing agent are inherent in ozone due to the structural features of the molecule and the mobility of one of the oxygen atoms, which, splitting off, turns the gas into oxygen: O3 → O2 + O ·
Oxygen (the brick from which the molecules of substances such as oxygen and ozone are built) is a chemical element. As it is written in the reaction equations - O. Ozone oxidizes all metals except for gold, platinum and its subgroups. It reacts with gases in the atmosphere - oxides of sulfur, nitrogen and others. Organic substances do not remain inert either; the processes of breaking multiple bonds through the formation of intermediate compounds are especially fast. It is extremely important that the reaction products are harmless to the environment and humans. These are water, oxygen, higher oxides of various elements, carbon oxides. Binary compounds of calcium, titanium and silicon with oxygen do not interact with ozone.
Application
The main area where "smelling" gas is used isozonation. This method of sterilization is much more efficient and safer for living organisms than disinfection with chlorine. When purifying water with ozone, the formation of toxic methane derivatives, replaced by dangerous halogens, does not occur.
Increasingly, this environmentally friendly sterilization method is being used in the food industry. Refrigeration equipment, food storage facilities are treated with ozone, and odors are eliminated with it.
For medicine, the disinfecting properties of ozone are also indispensable. They disinfect wounds, saline solutions. Venous blood is ozonated, and a number of chronic diseases are treated with a “smelling” gas.
Being in nature and meaning
Simple substance ozone is an element of the gas composition of the stratosphere, a region of near-Earth space located at a distance of about 20-30 km from the surface of the planet. The release of this compound occurs during processes associated with electrical discharges, during welding, and the operation of copier machines. But it is in the stratosphere that 99% of the total amount of ozone in the Earth's atmosphere is formed and contains.
Vitally important was the presence of gas in near-Earth space. It forms in it the so-called ozone layer, which protects all living things from the deadly ultraviolet radiation of the Sun. Oddly enough, but along with great benefits, the gas itself is dangerous for people. An increase in the concentration of ozone in the air that a person breathes is harmful to the body, due to its extreme chemical activity.
