| Chlorine, A Report Essay, Research Paper
Chlorine, symbol Cl, is a greenish-yellow gaseous element. In group 17 of the periodic table, chlorine is one of the halogens. The atomic number of chlorine is 17. Chlorine is a greenish yellow gas, which combines directly with nearly all elements. It is a gas at normal temperature and pressure, but because it is highly reactive it is not found as a gas in nature. Instead, it appears as naturally occurring organochlorine compounds and salts. It is commonly found as NaCl (solid or seawater). The gas has an irritating odor and in large concentration is dangerous; it was the first substance used as a poison gas in World War I (1914-1919). Other basic information includes the facts that chlorine melts at -101. C (-149.8. F), and boils at -34.05. C (-29.29. F) at one atmosphere pressure; the atomic weight of the element is 35.453.
Chlorine was first isolated in 1774 by the Swedish chemist, C. W. Scheele , who thought that the gas was a compound; it was not until 1810 that the British chemist Sir Humphry Davy proved that chlorine was an element and gave it its present name.
Chlorine has a huge variety of uses: as a disinfectant and purifier, in plastics and polymers, solvents, agrochemicals and pharmaceuticals, as well as an intermediate in manufacturing other substances where it is not contained in the final product.
Chlorine is used worldwide to purify water supplies as the ultimate defense against waterborne microbiological infection. Modern day cholera epidemics in Peru, China, India or Africa exemplify the devastating consequences of poor sanitation.
Chlorine also plays a critical role in the production of thousands of commercial products. Products reliant on chlorine’s unique properties include everyday household items such as household bleach and swimming pool disinfectants to bullet-resistant vests, computer hardware, silicon chips and automotive parts.
Chlorine and its derivatives are essential to many sectors, including healthcare and the automotive, electronic, building and textile industries, as well as water treatment. Chlorine and its derivatives are fundamental.
Not only does mankind benefit from this versatile and ubiquitous chemical, but so does nature. Chlorine is a highly reactive element, which does not exist by itself in nature, but only in combination with other elements. It is one of the most common elements in nature, where it is even more plentiful than carbon. Key natural sources of organochlorines are the oceans, forest fires and fungal activity.
Natural organochlorines are produced as a result of natural chlorine reacting with organic material in the environment. They have some surprising sources and properties: an Ecuadorian tree frog produces a chlorinated alkaloid, with pain-killing properties several hundred times more powerful than morphine; a natural organochlorine antibiotic, vancomycin, is our last defense against hospital Staphylococcus infections; and some natural organochlorinated products exhibit potent antibacterial and anticancer properties.
Organohalogens – organic compounds containing chlorine, bromine, iodine or fluorine – have been made in nature since prehistoric times. Deposits have been found in lignite samples 15 million years old and bituminous coal 300 million years old.
Living organisms produce over 3,000 organohalogens, of which more than half contain chlorine. Chlorine-based compounds are made by marine organisms (sponges, corals, sea slugs, jellyfish and seaweeds), plants, seeds, fungi, lichens, bacteria, freshwater algae and insects. These naturally occurring organohalogens play an essential role in the survival of these organisms.
On land, some 300 natural chlorine-based compounds are known to be produced by terrestrial fungi and plants. These range from the chloromethane released by wood-rotting fungi to complex chlorinated polyacetylenes made by plants of the Aster family. In terrestrial plants, organochlorines often act as anti-feedants to protect the plant from attack by insects or herbivores.
So, as you can see, chlorine is a very essential element in life.
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