Carbon
Main properties and application areas
Carbon (C) holds sixth place on Mendeleev’s periodic table of elements. Carbon has been known since ancient times. Primitive people noticed that after wood burned, charcoal formed, which they could use to draw on the walls of caves. Carbon is found in the composition of every organic compound. The two most widely studied allotropic modifications of carbon are graphite and diamond.
Graphite is a soft, black substance which easily leaves traces on paper, and has a metallic shine. Additionally, graphite is an excellent conductor of heat and electricity. Graphite is used in industry for manufacturing graphite lubricants, and also for making pencils.
Unlike graphite, the structure of another allotropic modification, diamond, resembles a tetrahedron. Besides carbon, diamond is made up of chromium, silicon, aluminum, manganese, titanium and iron. After carbon, nitrogen is the largest component in diamond. Owing to its structure, it does not conduct electricity and has weak heat conductivity. Diamonds are used for making precious stones. Artificially created diamonds are used for making cutting tools and abrasive materials.
Another allotropic modification of carbon is the fullerene. The fullerene consists of many carbon atoms connected by covalent bonds. The molecules in the complex structure of the fullerene are held together by electrostatic and Van der Waals forces. The properties of fullerenes have not been fully studied. But we do know that this allotropic modification of carbon can be used for manufacturing medicine thanks to its ability to absorb free radicals.
The chemical properties of carbon
1. Carbon is a non-metal and can interact with the metal elements with the formation of carbides:
Ca + 2C = CaC₂
2. The combustion reaction of carbon in an oxygen environment takes place in two stages:
2С + O₂ = 2CO
2СO₂ + О₂ = 2СО₂
3. In certain conditions, as a result of combining carbon and hydrogen, an organic substance is formed- methane:
С + 2H₂ = CH₄
4. If water evaporates on hot coal, carbon dioxide and hydrogen forms:
C + H₂O = CO + H₂
5. Reacts with fluorine. Carbon does not react with chlorine, bromine or iodine:
С + 2F₂ = CF₄
6. Carbon compounds with sulfur are possible:
С + 2S = CS₂
7. Carbon can reduce metals from their oxides:
2ZnO + C = 2Zn + CO₂
8. It can also interaction with sulfuric acid at a high reaction temperature:
C + 2H₂SO₄ = CO₂ + 2SO₂ + 2H₂O
You’ll understand these properties better by conducting a few visual experiments.
Carbon in organic chemistry
Carbon holds a special place on the periodic table. Thanks to its structure, it can form long chains of bonds of a linear or cyclical structure. At present over 10 million organic compounds are known. The diversity of organic compounds is very high, but at a high temperature they will always transform in air into the end products of carbon dioxide and water.
So the importance of carbon and its contribution to everyday life is enormous. One of the main biological processes, photosynthesis, will not take place without carbon dioxide.
Application of carbon
Carbon is widely used in medicine to make various kinds of medicine of an organic nature. Thanks to carbon isotopes, radiocarbon analysis is possible. The metallurgical industry could not function without the use of carbon. The carbon burnt in solid-fuel pyrolysis furnaces serves as a source of energy. In the petroleum industry, petrol and diesel fuel are manufactured from organic compounds of carbon. Carbon is an important ingredient in the manufacture of sugar. A synthesis of different organic compounds is used in all spheres of everyday life.