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What are halogens? Chemical elements of fluorine, chlorine, iodine and astatum

All the elements of Mendeleyev's periodic table are grouped together, depending on their chemical properties. In this article, we will analyze what halogens (or halides) are.

Definition of halogens

Halogens are elements from the periodic table of Mendeleev Group 17, and according to the outdated classification - the 7 main subgroup. Only 5 chemical elements belong to halogens, including fluorine, chlorine, iodine, astat and bromine. All of them are nonmetals. Halogens are very active oxidants, and at the outer level these elements have 7 electrons.

What are halogens, why did they get that name? The word "halogen" is derived from two Greek words, which together mean "the birth of salt." One of the elements of this group is chlorine, together with sodium forms salt.

Physical properties of the halogen group

The chemical properties of halogens are similar, but the physical characteristics of the elements differ from each other.

Fluoride is a gaseous substance of yellow color, with a very unpleasant and sharp odor. Chlorine is a green-yellow gas with a heavy and repulsive flavor. Bromine is a brown liquid. Astat is a blue-black solid with a sharp odor. Iodine is a gray solid. Summarizing the above information, one can answer the question: "What are halogens?". These are gases, liquids, and solids.

Chemical properties of the halogen group

The main common property of all halogens is that they are all very active oxidants. The most active halide is fluorine, which reacts with all metals, and the most inactive is astatine.

Interaction with halogens for simple substances (except for some nonmetals) is easy. In nature, they are found only in the form of compounds.

Fluorine

Such a chemical element as fluorine was obtained only in the late 19th century by a French scientist named Henri Moissan. Fluoride is gas of pale yellow color. Halogens are typical non-metals and oxidants, and fluorine from all halogens is the most active. Now this halogen is indispensable in the industry because it is used in the manufacture of pipes, insulating tape, various fabric coverings, non-stick surfaces for frying pans and molds, and in medicine for the manufacture of artificial arteries and veins. In industry, this halogen is diluted with nitrogen.

Chlorine

Chlorine is a famous chemical element, belongs to the group of halogens. What are halogens, we dismantled above. Chlorine retains the basic properties of the elements of its group.

The name he received from the Greek word "chloros", which translates as pale green. This gas is very widespread in nature, it is found in large quantities in sea water. Chlorine is a very important chemical element, it is practically indispensable for bleaching, disinfection of pools, and also disinfection of drinking water.

But chlorine is also known for being the most dangerous deadly weapon. In 1915, German troops used about 6,000 cylinders with this halogen against the French army. This deadly weapon was invented by the famous German chemist Fritz Haber.

Iodine

Iodine, or iodine, is another chemical element that belongs to the halogen group. In fact, in the Mendeleev table, this element is called iodine, but iodine is considered its trivial name. The name of the element is derived from the Greek word, which means "violet" in Russian. This chemical element in everyday life occurs quite often. When interacting with other halogens, mainly chlorine, an excellent means for disinfecting wounds and scratches is obtained. Now iodine is used in medicine for the prevention of thyroid disease.

Astat

Astat is interesting in that it was never received by chemists in such quantity that it could be seen with the naked eye. And most likely, this opportunity will never be presented to them. If specialists could obtain a large amount of this chemical element, it would immediately evaporate, due to the occurrence of a high temperature, which appears as a result of the radioactive radiation of this element. Astat is the rarest chemical element, and a small amount is contained in the earth's crust.

Among halogens, astat is a rather useless element, because at the moment no application has been found to it.

Application and meaning

Despite the fact that all halogens have similar chemical properties, they are used in completely different areas. For example, fluoride is very useful for teeth, which is why it is added to toothpastes. The use of therapeutic and prophylactic agents, which contain a chemical element of fluoride, prevents the appearance of caries. Chlorine is used to produce hydrochloric acid, which is indispensable in industry and medicine. Chlorine is used for the manufacture of rubber, plastics, solvents, dyes, as well as synthetic fibers. The compounds containing this element are used in agriculture for pest control. Halogen chlorine is indispensable for bleaching paper and fabrics. It is believed that the use of chlorine for the treatment of drinking water is unsafe. Bromine, which is a halogen, and also iodine is often used in medicine.

The significance of halogens in human life is enormous. If we imagine the existence of mankind without halogens, then we would be deprived of such things as photographs, antiseptic and disinfectants, rubber, plastic, linoleum and many others. In addition, these substances are necessary for the human body to function properly, that is, they play an important biological role. Although the properties of halogens are similar, their role in industry and medicine is different.

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