While it was quickly replaced by the more deadly phosgene and mustard gases, chlorine gas has been used as a weapon as recently as in Iraq during the second gulf war. Chlorine was also once used to make a series of aerosol solvents and refrigerants called chlorofluorocarbons or CFCs.
However their use was stopped once it became apparent that when in the atmosphere these compounds absorb ultraviolet light and cause homolytic bond fission producing a chlorine free radical which in turn reacts with ozone. This has led to a reduction in the concentration of ozone in the so-called ozone layer, and therefore a reduction in the protection for those of us on the surface of the planet making us more susceptible to skin cancers.
So, that's chlorine - a Jeckll and Hyde element with an extremely wide range of applications. So slap on your sun screen. Tim Harrison was telling the tale of Element number 17, and that's chlorine. Tim's based at the University of Bristol's ChemLabs. Next week, the stuff that gives itself an x-ray. This grey metallic element gives off beta particles as it decays.
These can cause radioactive damage in their own right, but prometheum is probably most dangerous because those beta particles generate X-rays when they hit heavy nuclei, making a sample of promethium bathe its surroundings in a constant low dosage x-ray beam. It was initially used to replace radium in luminous dials. Promethium chloride was mixed with phosphors that glow yellowy-green or blue when radiation hits them.
However, as the dangers of the element's radioactive properties became apparent, this too was dropped from the domestic glow-in-the-dark market, only employed now in specialist applications.
And you can hear what some of those applications are when Brian Clegg looks at the story of promethium in next week's Chemistry in its Element. In the meantime more elements are available from the Chemistry in its Element podcast, that's on iTunes or on the web at chemistryworld. I'm Chris Smith, thank you very much for listening and goodbye. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists.
There's more information and other episodes of Chemistry in its element on our website at chemistryworld. Click here to view videos about Chlorine. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback.
Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists.
Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium.
G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership. Facebook Twitter LinkedIn Youtube. Discovery date. Discovered by. Carl Wilhelm Scheele.
Origin of the name. The name is derived from the Greek 'chloros', meaning greenish yellow. Melting point. Boiling point. Atomic number. Relative atomic mass.
Key isotopes. Electron configuration. CAS number. ChemSpider ID. ChemSpider is a free chemical structure database. Electronegativity Pauling scale.
Covalent bond. Found in. CCl 4. Common oxidation states. Atomic mass. Half life. Mode of decay. Relative supply risk. Crustal abundance ppm. Top 3 producers. Top 3 reserve holders. Political stability of top producer. Political stability of top reserve holder. Young's modulus GPa. Shear modulus GPa. Bulk modulus GPa. Vapour pressure. Temperature K. Pressure Pa. Listen to Chlorine Podcast. In his report on the Economics of Chlorine, D.
Pritchard concludes "The [chlor-alkali] industry in North America has had to manufacture and sell cheaply, find markets and new uses, switch largely from bleaching powder to liquid chlorine, provide technical service, and adjust more or less imperfectly the economics of three distinct substances evolved in one major operation to a rapidly changing industrial structure, and do it all in about 16 years. A capacity bearing a reasonable relation to consumption, a decent return on its capital, and the continuance of research are essential to this key industry.
In January , when Eben C. Speiden was contacting chlorine producers in the U. The original activities of the Chlorine Institute, therefore, were structured as the charter dictated, " The first three committees remained active through , and CI's Transportation Committee remains active to this day as the Transportation Issue Team. Development of a practical method of bleaching 'kraft' pulp, which makes possible the production of heavy-duty paper in white and pastel shades. Soon it became apparent that many such activities truly were the responsibility of the individual companies.
Therefore, the Chlorine Institute's efforts then focused on what today remains CI's core mission: the safe production, distribution and use of chlorine as well as the security of chlorine handling operations.
Water and wastewater treatment plants use chlorine to reduce water levels of microrganisms that can spread disease to humans disinfection. Exposure to chlorine can occur in the workplace or in the environment following releases to air, water, or land. People who use laundry bleach and swimming pool chemicals containing chlorine products are usually not exposed to chlorine itself.
Chlorine is generally found only in industrial settings. Chlorine enters the body breathed in with contaminated air or when consumed with contaminated food or water. It does not remain in the body, due to its reactivity. Effects of chlorine on human health depend on how the amount of chlorine that is present, and the length and frequency of exposure. Effects also depend on the health of a person or condition of the environment when exposure occurs. Breathing small amounts of chlorine for short periods of time adversely affects the human respiratory system.
Effects differ from coughing and chest pain, to water retention in the lungs. Chlorine irritates the skin, the eyes, and the respiratory system. These effects are not likely to occur at levels of chlorine that are normally found in the environment.
Human health effects associated with breathing or otherwise consuming small amounts of chlorine over long periods of time are not known. Some studies show that workers develop adverse effects from repeat inhalation exposure to chlorine, but others will not.
Chlorine dissolves when mixed with water. It can also escape from water and enter air under certain conditions. Most direct releases of chlorine to the environment are to air and to surface water. Once in air or in water, chlorine reacts with other chemicals. It combines with inorganic material in water to form chloride salts, and with organic material in water to form chlorinated organic chemicals.
Because of its reactivity chlorine is not likely to move through the ground and enter groundwater. Plants and animals are not likely to store chlorine.
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