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Radon Essay Research Paper Mal SchulerChem H

Radon Essay, Research Paper

Mal SchulerChem H Period DMs. Watson5/1/99RADON Radon is the sixth and last member of the inert gas series, group O of the periodic table. Discovered in 1900 by F.E. Dorn, this element was called radium emanation, but when isolated by William Ramsay and Robert Whytlay-Grey inn 1908 the name was changed to niton, from Latin, meaning “shining”. It has been known as radon since 1923 and is given the symbol Rn. The atomic weight of radon is about 222 and the atomic number is 86. An approximate calculation indicates that every 2.6 sq km of soil to a depth of 15cm contains about 1 gram of radon- emitting radium, and that radon makes up more than half of normal background radioactivity in the environment.(Brown p23) Radon is a radioactive gas of which twenty isotopes are known, including radon- 222 from radium, with a half life of 3.823 days, and radon- 220, also called thoron, from thorium, with a half- life of 54.5 seconds. Both isotopes emit alpha particles.(Kokotti p 2249) The melting point of the element is -71 deg C, the boiling point is -61.8 deg C, and the gas density is 9.73 g/l at 0 deg C. Recent reports have indicated a reaction may occur between radon and fluorine, forming radon fluoride. At room temperature radon is a colorless gas, but when cooled below its freezing point the solid exhibits a brilliant phosphorescence that becomes yellow as the temperature is lowered, and orange- red at intense temperatures. Radon has been used therapeutically as an alpha- particle source in the treatment of cancer.(Wu p.488) Unsafe levels of radon gas have been discovered in a number of homes throughout the United States. Apparently, radon-222, produced by natural radium in the ground, can enter a house through small fissures or in well water, and remain in the air if unventilated.(Gammage p.2238) The radon then decays to radioactive products that can be absorbed in the lungs and can lead, over a long period of time and exposure, to lung cancer deaths. The U.S Environmental Protection Agency has estimated that from 5,000 to 20,000 lung- cancer deaths each year may be attributed to radon products. It recommends remedial action if radon levels in homes exceed 4 trillionths of a curie of radon per liter of air.(Pontius p.20) Although initial discoveries pointed to particular areas susceptible to radon pollution, such a Maryland and eastern Pennsylvania, and in a number of European countries. So far, proposed remedies for indoor radon pollution have ranged fairly widely in cost, but the simplest methods of dealing with the problem are relatively inexpensive. One, is buying a kit which you plug into a wall shock. This kit will measure the amount of radon in a house and an alarm will go off when there is to much radon present in the house.(Cavallo p. 2254) Three British scientists claim they have found previously unsuspected link between radon gas and certain non- lung cancers. Radon has been known for decades to cause lung cancer, but a study in the journal “Lancet” links radon exposure and leukemia in both children and adults; brain, spine, bone and skin cancer in children; and kidney and skin cancer in adults.(Chah p.1793) In conclusion radon is very deadly because it cause many disease that can lead to death. The simplest method of protecting you and your family is buying a kit which measures the level of radon present in a house.Bibliography Brown, William.(1992). Craves risk cancer from undergroung radon: New Scientists. V. 135 Sept. p.23 Cavallo, A.(1992). Uce of natural basement ventilation to control radon in single family dwellings: Atmosheric- Environment-General topics. V. 26A no9 June p 1791-3 Chah, B. (1992). Determination of radon in indoor air in Quebec by liquid scintillation counting in ortho-xylene: Atmosheric-Environment-General topics. V.26A no9 June p. 1791-3 Gammage,R. (1992). Subteranean transport of radon and elevated indoor radon in hilly karst terrain: Atmosheric- Environment-General topics. V.26A no 12 Aug. p. 2237-46 Kokotti, H. (1992). Dependency of radon entry on pressure difference: Atmospheric-Environmental-General topics. V. 26A no 12 Aug. p. 2247-50 Pontius, Frederick. (1992). USEPA’s proposed radon MCL: too high, too low, or just right?:American water works association journal. V. 84 Oct. p. 20+ Wu, Chai Wah.(1992). A two layer radon transform cellular neural network: IEEE- Transactions on circuits and systems. V.39 July. p.488-9




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