Ng1 DarianNg Chemistry Mr.Betancourt 3April2009 TheWondersofChlorine Haveyoueverwonderedwhyyourswimmingpoolsmelledsobad?Orwhyitseemslike yourliquidbleachseemslikethesamesmellastheswimmingpool?Theanswerischlorine. Chlorineisresponsibleforthecreationofbleachandchloridethatcleanstheclothesandwater weuse.Wearealwaysexposedtochlorinebecauseitsarounduseveryday.Chlorinecanbe foundthroughouttheoceanandsaltmines.Everypieceofpaperyouuseinschooloratwork, youareexposedtochlorinebecauseatrecycleplants,chlorineisusedtocleanpaperforreuse. Notonlyareweexposedtochlorineeveryday,buthumansalsohaveagreatneedtomass producethischemicalinorderformanyofourbasicneedstobemet.Forexample,liquidbleach isusedinordertohavecleanclothesandfordrinkablefountainwater.However,toomuch chlorineisnotalwaysagoodthing.Massproductionmeansmasstransportation,whichcanlead todisastrouseventsifthispoisonousgreenishyellowgaswastobereleasedinplaceslikeNorth Carolina,leadingmanytowonderifchlorineisworthit.Overexposuretochlorine,suchasbeing aroundthehouseholdanddrinkingwater,canbehazardoustoAmericansandcausedangerous effects. Historical Context Chlorinehasbeenaroundforovertwohundredyearsandisoneofthemostwidelyused

elementsintheworld,rangingfrompoisonousgasestochlorinebleaches.Fromthebattlefields ofEuropetoCaliforniafactories,chlorinehasmadeamarkonthelandscapewithitspowerful odorandextremelydangeroustoxicity.Throughouthistory,theusageofchlorinehas

Ng2 changeddramaticallyforgoodorfortheworse. Chlorineisapoisonous,yellowishgreengasfirstdiscoveredbyCarlWilhelmScheelein 1774duringhisinvestigationofthemineralpyrolusite.Heheatedpyrolusitewithhydrogen chloride,resultingthisgreenishyellowgas.However,CarlWilhelmthoughtthiswasacompound ofoxygenandfirstnameditdephlogisticated muriatic acid. Meanwhile, another man believed this dephlogisticated muriatic acid was made of an oxygen and an unknown element yet to be discovered, muriaticum. (Stwertka , 69) Despite his best efforts, he was unsuccessful in decomposing the compound because he thought he could breakdown the element chlorine. In 1810, the English chemist Sir Humphry Davy also tried to do this separation, but to no ones surprise, he also failed. As a result of the many failed experiments, he concluded that this greenish-yellow gas is in fact a new element and became what we now know as the 17th element of the periodic table Chlorine. Sir Humphry Davy named this element chlorine based on its yellow-greenish color of the gas where he derived it from the Greek word chloros meaning yellow green or light green. (Heiserman,70)

This greenish-yellow gas can be found in many natural places like seawater and in deposits of salt mines. However, that is not most known to the general people. Chlorine is mostly found in household cleaning products of bleach. The bleaching action of chlorine is its best-known property. (Heiserman , 70) Early research of using chlorine to clean clothes failed because the first solution was called hydrochloric acid, which unfortunately dissolved cotton and linen destroying many pieces of clothing made of such material. After many years of research, the familiar liquid bleach was created and used in all households today was developed. This bleach contains a weak solution of sodium hypoclorite cleans your clothes. (Heiserman,71)

Ng 3 Chlorine is used for disinfecting swimming pools and drinking water from public fountains and taps. The toxic properties of chlorine makes it an excellent choice for disinfecting water for human usage. However, with such a dangerous material, there will always be negative outcomes. In World War I, where chlorine was used as a poison gas in the form of the tear gas grenade, created by the French in August of 1914. It was later researched and developed for widespread use by the Germans. These types of gases were first used widespread against the French on August 22, 1915. Greenishyellow clouds approached the Western Front and nearly decimated the entire regiment stationed for battle by destroying their internal respiratory organs

causing breathing problems and choking attacks. (Duffy) Although the use of chlorine in gas grenades have nearly disappeared, people are still exposed to chlorine throughout the world. One such exposure is in paper recycling plants where they use chlorine to rid paper of the ink thats already written on top. Inhaling enough of the chlorine fumes can cause breathing problems for workers and great exposure can cause permanent damage for workers leaving a scar in their respiratory system. Chlorine Characteristics Chlorine has been used throughout history and is continually used today making chlorine one of the top 10 most produced chemicals by the United States. (LockPortNY ) From the time of chlorines discovery to when it is massively produced, humans have learned how to fully take advantage of the element chlorine in multiple ways, both helpful and damaging. Chlorine is part of the group of elements called halogens. Halogens are a group of nonmetal elements that are highly reactive and can be harmful or lethal to many biological organisms if appears in sufficient quantities. This high reactivity is due to the atoms being one electron short of a full outer shell of eight electrons. Chlorine is a pale green gas thats about 2.5 times as dense as air with a suffocating odor that is chocking and poisonous. (FactsAboutChlorine.)Chlorines structure pictured below is of a circular bubble because chlorine is

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formed by covalent bonds of chlorine coming together. The boiling and melting points are 239.11 kelvin and 171.6 kelvin respectively. (Lenntech)

^structure of chlorine (FactsAboutChlorine.) Chlorine has always been known for the dangers that can be caused from its toxicity, but how exactly does chlorine affect humans and other animals alike? The answer lies deep within your own respiratory and cells. Chlorine concentration can be detected as low as one part per million molecules or atoms due to its irritation on exposure to humans causing severe burning in the eyes, nose, skin, and lungs. At 30 parts per million, major pain is experienced with coughing and vomiting. At 60 parts per million, lung damage starts to be felt. As the parts per million increases, the chance of death increases. At 430 parts per million, death can be ensured in as little as 30 minutes. While at 1,000 parts per million (0.1%), death occurs within a few minutes after a few deep breaths of the gas. (LockPortNY) This is the result of chlorines oxidizing powers, which can be good, but deadly to

humans. With enough concentration of chlorine, approximately 60 parts per million, chlorine gas will combine with water in the air or body to form Hydrochloric acid and liberate nascent oxygen, which would attack your tissues in your body, like your lungs. (LockPortNY) Ng 5 Community Effects One devastating accident occurred in South Carolina involving a chlorine accident when a 42 car freight train slammed into a parked train on a side track in the small town of Graniteville, South Carolina. Fourteen cars on the moving derailed, including three chlorine tank cars, one of which leaked a deadly cloud of greenish-yellow gas into the air. Six textile mill workers, along with the train engineer; a truck driver and a man who was found in his Main Street home, died of chlorine inhalation. (Akin) Despite the nine deaths, there were at least 234 people went to area hospitals, most with respiratory illness from inhaling chlorine gas. Of all the people who went to the hospital, 38 were hospitalized for more than a day and five were in critical condition. Authorities ordered all 5,400 people within a mile of the railroad crash to evacuate because of the dangers of Chlorine gas that resulted from the train crash. An estimated 60-70 tons of choking, toxic plumes escaped from the leaking car. All these accidents resulted from just one element combining with the water vapors in the air that causes the disastrous effects. (Akin)

Chlorine gas is floating in the air after being mixed with water. Inhaling a few breaths of this can have devastating effects on your lungs. (Akin) However, not all communities are affected as greatly with chlorine exposure. Factory workers in the VanDeMark Chemical complex that handle chlorine on a daily basis, but they do not have as much of an after effect of inhaling chlorine gas. Because there are health hazard restrictions, Ng 6 such as a limit of chlorine handled at a time and gas masks while producing the poison gas, phosgene out of chlorine. Despite the safety measures, these workers still face respiratory to the lungs and have irritated skin. Although great exposure to Chlorine will cause skin and respiratory damage, chlorine is still used in all water systems in America. Many may think that this will cause breathing problems, but in fact, the amount of chlorine used in water is far too small parts per million to cause any great damage. According to the San Francisco water system, the maximum allowed amount of chlorine is one part per ten million. (SanFranciscoPublic UtilitiesCommission)However, the water in San Francisco is used at one part per thirty million. With such facts and numbers, one can conclude that

despite being constantly exposed to chlorine, there will not be any harmful effects on the body. Chlorines usefulness outweighs the dangers of this greenish yellow gas. Chlorine has been around for hundreds of years providing great mysteries in the science world like using chlorine as the base material for tear gas. Scientists have explored many ways to exploit its usefulness for the greater good like creating cleaning supplies. Although chlorine can attack your body dangerously like those who fell victim to the chlorine leak in North Carolina, it can only be achieved with concentrations of 500 parts per million or more, but water in the United States use chlorine in one part per ten million. The oxidizing powers that clean swimming pools and water are around Americans everyday whether its on a piece of paper or in the dry cleaners. This same oxidizing power, however, can destroy the lungs of many human beings because chlorine burns the tissue cells of humans causing respiratory problems. Exposure to too much chlorine will have dangerous effects to Americans, which happens everyday, but Americans should not worry about being poisoned by chlorine. As long as regulations of the amount of chlorine used to clean water are followed, there should be no worries of chlorine outbreaks, but how safe are these regulations?

Ng 7 Works Cited 1. Duffy, Michael. Weapons of War Poison Gas First World War. Ed. Duffy, Michael. 5 May 2002. 14 March 2009 2.SanFranciscoPublicUtilitiesCommission.19March2009.19March2009. 3.LockPortNY.1998.6March2009 4.FactsAboutChlorine.CenterforDiseaseControlandPrevention.25March2005.13Feb. 2009 5.Lenntech.2008.13Feb.2009 6.Akin."ChlorineGasFromSouthCarolinaTrainCrashKillsNine."Ensnewswire.com10 Jan.2005.1March.2009http://www.ensnewswire.com/ens/jan2005/2005011004.asp 7.Heiserman,DavidL.ExploringChemicalElementsandtheirCompounds.BlueRidgeSummit :TABBooks,1992 8.Stwertka,Albert.AGuidetotheElements.NewYork:OxfordUniversityPress,Inc,2002.