What is metal? Properties and features of metals

What is metal? The nature of this substance was of interest in ancient times. About 96 types of metals have been discovered . About their characteristics and properties and talk in the article.

What is metal?

The greatest number of elements in the periodic table belongs to metals. At present, only 96 species are known to humans. Each of them has its own characteristics, many of which have not yet been studied.

What is metal? This is a simple substance, which is characterized by large electrical and thermal conductivity, a positive temperature coefficient of conductivity. Most metals have high strength, ductility and can be forged. One of the distinguishing features is the presence of metallic luster.

The meaning of the word "metal" is associated with the Greek métallion, where it means "digging out of the earth", as well as "mine, mine". In the Russian terminology, it came during the reign of Peter I from the German language (German Metall), in which the word moved from Latin.

Physical properties

Elements metals usually have good ductility, except for tin, zinc, manganese. In terms of density, they are divided into light (aluminum, lithium) and heavy (osmium, tungsten). Most have a high melting point, the total range ranges from -39 for mercury to 3410 degrees C for tungsten.

Under normal conditions all metals, except mercury and France, are solid. The degree of their hardness is determined in points on the Moss scale, where the maximum is 10 points. So, the hardest are tungsten and uranium (6.0), the most mild is cesium (0.2). Many metals have silvery, bluish and gray hues, only some are characterized by yellow and reddish colors.

In their crystal lattices there are mobile electrons, due to which they perfectly conduct electric current and heat. Silver and copper work best. Mercury is the lowest heat conductivity.

Chemical properties

By chemical properties, metals are divided into many groups. Among them are alkaline, alkaline earth, light, actinium and actinides, lanthanum and lanthanides, and semimetals. Separately there are magnesium and beryllium.

As a rule, metals act as reducing agents for nonmetals. They have different activities, so reactions to substances are not the same. The most active are alkali metals, they easily interact with hydrogen, water.

Under certain conditions, the interaction of metals with oxygen almost always occurs. The reaction to it is absent only in gold and platinum. They also do not react to sulfur and chlorine, unlike other metals. Alkaline group is oxidized in ordinary medium, the rest under high temperatures.

Being in nature

In nature, metals are found mainly in ores or compounds, for example, oxides, salts, carbonates. Before use, they undergo long cleaning steps. Many metals accompany mineral deposits. Thus, cadmium is a part of zinc ores, scandium and tantalum are adjacent to tin.

Immediately in pure form there are only inert, that is, inactive metals. Because of their low susceptibility to oxidation and corrosion, they have won the title of noble. They include gold, platinum, silver, ruthenium, osmium, palladium, etc. Noble metals are very plastic and have a characteristic bright shine in finished products.

Metals surround us everywhere. In large quantities, they are found in the earth's crust. The most common are aluminum, iron, sodium, magnesium, calcium, titanium and potassium. They are contained in sea water (sodium, magnesium), are part of living organisms. In the human body, metals are present in the bones (calcium), in the blood (iron), the nervous system (magnesium), muscles (magnesium) and other organs.

Study and use

What is metal already known to ancient civilizations. Among the Egyptian archaeological finds, dating from 3-4 millennium BC, were found products of precious metals. The first man discovered gold, copper, silver, lead, iron, tin, mercury. They served for the manufacture of jewelry, tools, ritual objects and weapons.

In the Middle Ages antimony, arsenic, bismuth, zinc were discovered. They were often given magical properties, connected with the cosmos, the movement of the planets. The alchemists conducted numerous experiments in the hope of turning mercury into water or gold. Gradually, the number of discoveries increased, and by the 21st century all metals known to date had been discovered.

Now they are used practically in all spheres of life. Metals are used to make jewelry, equipment, ships, cars. Of these, skeletons are made for the construction of buildings, they make furniture, various small details.

Excellent electrical conductivity has made the metal indispensable for the manufacture of wires, it is thanks to him, we use electric current.