Without carbon, life would be impossible! Yet carbon makes up less than 0. 03 percent of the earths crust. Pure carbon exists in nature in the form of diamonds, and in graphite. Both forms are pure carbon with different crystal structures.
Another form of pure carbon, called amorphous carbon, consists of graphite-like particles too tiny to see without a microscope. Diamonds and graphite have important industrial uses. But much of the carbon used in industry is amorphous carbon. Amorphous carbon and ash result when materials containing carbon are burned or heated without enough oxygen for them to burn completely. For example, if oil, natural gas, or other petroleum fuels are burned in limited supplies of air, powdery-black soot of amorphous carbon, called carbon black, is formed.
Carbon black is used in rubber products and paint. Charcoal is used as a cooking fuel and ivory black, made by heating ivory, is used as a pigment in paint. Most carbon occurs in combination with other elements. For example, the carbon dioxide in the air is a compound of carbon and oxygen.
Other compounds containing carbon include minerals such as limestone, and fuels such as coal and petroleum. Carbon compounds make up the living tissues of all animals and plants. There are over one million known carbon compounds (still growing rapidly every year), which is over the sum total of all the other elements combined. The largest group of these compounds are the ones composed of carbon and hydrogen. Carbon also forms another series of compounds, which is classified as inorganic, but is a much smaller number than the organic compounds. These millions of compounds combine in various ways to produce an almost unlimited number of carbon-containing substances.
Organic chemistry, which is the name given to the study of compounds made by and derived from living organisms, is primarily a study of carbon compounds. Carbon and its compounds are found widely dispersed in nature. It is estimated that carbon makes up 0. 032% of the Earths crust. Free carbon is found in large deposits as coal, an amorphous form of the element that contains additional complex carbon-hydrogen-nitrogen compounds.
Pure crystalline carbon is found as graphite and in small amounts as diamonds. Extensive amounts of carbon are found in the form of its compounds. In the atmosphere, carbon is present in amounts up to 0. 03% by volume as carbon dioxide. Various minerals such as limestone, dolomite, marble, and chalk all contain carbon in the form of carbonate. All plant and animal life is composed of complex organic compounds containing carbon combined with hydrogen, oxygen, nitrogen, and other elements.
The remains of past plant and animal life are found as deposits of petroleum, asphalt, and bitumen. Deposits of natural gas contain compounds that are composed of carbon and hydrogen. The forms of pure carbon vary widely depending upon which crystal structure the atoms take. In diamond, the carbon atoms are arranged in a close framework that makes diamond one of the hardest substances known.
Diamonds are used to cut other hard materials. However, graphite is so soft that it is widely used to lubricate moving machine parts. Its carbon atoms are arranged in flat sheets or layers that can easily slide back and forth over each other. Carbon has many other uses, ranging from ornamental applications of the diamond in jewelry to the black-colored pigment of carbon black in automobile tires and printing inks. Another form of carbon, graphite, is used for high-temperature crucibles, arc light and dry-cell electrodes, lead pencils, and as a lubricant. It is also used in fishing rods, golf clubs, and tent poles.
Charcoal is used as an absorbent for gases and as a decoloring agent. The compounds of carbon also have many uses. Carbon dioxide is used for the carbonation of beverages, for fire extinguishers, and in the solid state as a refrigerant. Another oxide of carbon, carbon monoxide, finds use as a reducing agent for many metallurgical processes. Carbon tetrachloride and carbon disulfide are important solvents for industrial uses.
Gaseous dichlorodifluoromethane, commonly known as Freon, is used in refrigeration devices. Calcium carbide is used to prepare acetylene, which is used for the welding and cutting of metals as well as for the preparation of other organic compounds. Other metal carbides find important uses as refractories and metal cutters. At room temperature, pure carbon does not react chemically, but its compounds unite easily with other elements and compounds. Pure carbon will not dissolve in any common solvent.
At higher temperatures, carbon combines with oxygen, sulfur, certain materials, and elements of the halogen group. Carbon also forms the many organic compounds, which usually contain hydrogen and may contain other elements. From the Latin word “carbo,” meaning charcoal, Carbon has been known since ancient times, but was never recognized as an element until much later. It has the chemical symbol C. It does not melt, but it sublimes at about 3500 C. That means that it changes from a solid directly into a gas.
Carbons atomic number is 6 and its atomic weight is 12. 011. The nucleus contains 6 protons, with 6 electrons orbiting the nucleus. The outer four electrons can take part in chemical bonding. Its most common type of atom, or isotope, carbon 12, was adopted in 1961 as the standard for atomic weights with an assigned weight of 12. 0000.
BibliographyCarbon. McGraw-Hill Encyclopedia of Science and Technology 3 BOR-CLE. McGraw-Hill. 1992. Carbon. Colliers Encyclopedia 5 BURNAP to CHARM.
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Carbon. The Dorling Kindersley Science EncyclopediaDorling Kindersley Limited, London. 1993. Carbon.
The World Book Encyclopedia C-Ch. World Book, Inc. , USA. 1987.CHEMystery: The Periodic Table of the Elements.http://hyperion.advanced.org/3659/pertable/6.htmlDownloaded 10-26-98.Web Elements.http://www.shef.ac.uk/uni/academic/A-C/chem/web-elements/nofr-hist/C.html.Downloaded 10-26-98.Fun Facts about CarbonSymbol:CAtomic #:6Atomic Weight:12.01115Group #:14Very important elementNucleus contains 6 protons, with 6 electrons orbiting the nucleus and the outer four electrons can take part in chemical bondingAt least 1 million organic compounds, which is rapidly increasingMost common isotope Carbon 12Carbon makes up 0.032% of the Earths crustWithout carbon, life would be impossible!Pure carbon exists in nature in the form of diamonds, and in graphiteGraphite is used for high-temperature crucibles, arc light and dry-cell electrodes, lead pencils, as a lubricant, in fishing rods, golf clubs, and tent polesCharcoal is used as an absorbent for gases and as a decoloring agentCARBON IS FUN!!!