The most common metal in the earth's crust. Metals in nature
Metals are a group of elements,which have such unique properties as electrical conductivity, high heat transfer, positive coefficient of resistance, characteristic luster and relative ductility. This type of substance is simple in chemical compounds.
Classification by group
Metals are among the most commonmaterials that are used by mankind throughout its history. Most of them are in the middle layers of the earth's crust, but there are those that are hidden deep in the mountain beds.
At the moment, metals occupy most of the periodic table (94 of 118 elements). Of the officially recognized it is worth noting the following groups:
1.Alkaline(lithium, potassium, sodium, france, cesium, rubidium). Upon contact with water, they form hydroxides.
2.Alkaline earth(calcium, barium, strontium, radium). Density and hardness.3.Lungs(aluminum, lead, zinc, gallium, cadmium, tin, mercury). Due to their low density, they are often used in alloys.
4.Transitional(uranium, gold, titanium, copper, silver, nickel, iron, cobalt, platinum, palladium, etc.). Have a variable degree of oxidation.
5.Semi-metals(germanium, silicon, antimony, boron, polonium, etc.). In their structure they have a crystalline covalent lattice.
6.Actinides(americium, thorium, actinium, berkelium, curium, fermium, etc.).
7.Lanthanides(gadolinium, samarium, cerium, neodymium, lutetium, lanthanum, erbium, etc.).
It is worth noting that there are metals in the earth's crust and those that are not identified in the group. They include magnesium and beryllium.
In nature there is a separate classcrystallochemical codification. These elements include native metals. These minerals are unrelated to each other. Most often, native metals in nature are formed as a result of geological processes.In the crystalline state in the earth's crust45 substances are known. Most of them in nature are extremely rare, hence their high cost. The share of such elements is only 0.1%. It is worth noting that finding these metals is also a laborious and expensive process. It is based on the use of atoms with stable shells and electrons.
Native metals are also called noble metals. They are characterized by chemical inertia and stability of compounds. These include gold, palladium, platinum, iridium, silver, ruthenium, etc. Most often, copper is found in nature. Iron in its native state is present mainly in mountain deposits in the form of meteorites. The most rare elements of the group are lead, chromium, zinc, indium and cadmium.
Virtually all metals under normal conditionsdiffers firmness and firmness. The exception is France and mercury, alkali metals. The melting point for all elements of the group is different. Its range ranges from -39 to +3410 degrees Celsius. The most resistant to melting is tungsten. Its compounds lose their resistance only at temperatures above +3400 ° C. Lead-free metals and tin should be isolated from easily-molten metals.Also, the elements are divided relative to the density(light and heavy) and plasticity (hard and soft). All metal connections are excellent conductors. This property is due to the presence of crystal lattices with active electrons. The maximum conductivity is copper, silver and aluminum, a little less - sodium. It is worth noting the high thermal properties of metals. The best heat conductor is silver, the worst is mercury.
Metals in the environment
Most often such elements can be found in the formcompounds and ores. Metals in nature form sulfites, oxides, carbonates. To purify the compounds, it is first necessary to separate them from the ore. The next step will be doping and final processing.
In industrial metallurgy, black andcolored ores. The former are based on iron compounds, the latter on other metals. Precious metals are platinum, gold and silver. Most of them are in the earth's crust. Nevertheless, a small proportion is also in seawater.
There are noble elements even in living organisms. In humans, about 3% of metal compounds are contained. Mostly the body contains sodium and calcium, which act as an intercellular electrolyte. Magnesium is necessary for normal operation of the central nervous system and muscle mass, iron is useful for blood, copper for the liver.
Finding metallic compounds
Most of the elements are located under the uppera layer of soil everywhere. The most common metal in the earth's crust is aluminum. Its percentage varies within 8.2%. Find the most common metal in the earth's crust is not difficult, since it occurs in the form of ores.
Iron and calcium in nature are met a little less often. Their percentage is 4.1%. Next are magnesium and sodium - 2.3%, potassium - 2.1%. The remaining metals in nature occupy no more than 0.6%. It is noteworthy that magnesium and sodium can equally be extracted both in the ground and in seawater.Metal elements in nature are found inform of ore or in a native state, like copper or gold. There are substances that need to be obtained from oxides and sulphides, for example, hematite, kaolin, magnetite, galena, etc.
Production of metals
The extraction procedure of the elements is reduced to extractingmineral. The discovery of metals in nature in the form of ores is the simplest and most widespread process in a wide industry. To search for crystalline deposits, special geological equipment is used, which analyzes the composition of substances on a particular plot of land. More rarely, the finding of metals in nature reduces to a banal open-underground method.
After extraction there comes a stage of enrichment, when fromore mineral concentrate is extracted. To distinguish elements use wetting, electric current, chemical reactions, heat treatment. Most often, the separation of metallic ore occurs as a result of melting, that is, heating with recovery.
Extraction of aluminum
This process is handled by non-ferrous metallurgy. In terms of consumption and production, it is the leader among other branches of heavy industry. The most common metal in the earth's crust is very in demand in the modern world. In terms of production, aluminum is second only to steel.Most of this element is used inaviation, automotive and electrical industries. It is noteworthy that the most common metal in the earth's crust can be obtained and "artificial" way. For such a chemical reaction, bauxites will be required. Of these, alumina is formed. When this substance is combined with carbon electrodes and fluoride salt under the influence of electric current, it is possible to obtain pure aluminum ore.
The country-leader among the producers of thiscomponent is China. In the year 18.5 million tons of metal are smelted there. The company-leader in the similar rating for the extraction of aluminum is the Russian-Swiss association UC RUSAL.
Application of metals
All elements of the group are distinguished by their strength,impermeability and relative resistance to temperature effects. That's why metals are so common in everyday life. Today, they make electrical wires, resistors, equipment, household items.
Metals are the ideal structural andtool materials. Clean and combined alloys are used in construction. In engineering and aviation, the main compounds are steel and more solid bonds.