The iodine atoms are added as anions, and each has a 1− charge and a mass number of 127. The addition of small amounts of iodine to table salt (iodized salt) has essentially eliminated this health concern in the United States, but as much as 40% of the world’s population is still at risk of iodine deficiency. (credit a: modification of work by “Almazi”/Wikimedia Commons credit b: modification of work by Mike Mozart) (b) The addition of small amounts of iodine to salt, which prevents the formation of goiters, has helped eliminate this concern in the US where salt consumption is high. Other uses are in making pesticides, Mercury cells for caustic soda and chlorine production, dental preparations, anti-fouling paint, batteries, and catalysts.\): (a) Insufficient iodine in the diet can cause an enlargement of the thyroid gland called a goiter. and is used in mercury switches and other electronic apparatus. It is used in making mercury-vapor lamps and advertising signs, etc. The metal is widely used in laboratory work for making thermometers, barometers, diffusion pumps, and many other instruments. The triple point of mercury, -38.8344C, is a fixed point on the International Temperature Scale (ITS-90). Methyl mercury is a dangerous pollutant and is now widely found in water and streams. If it is necessary to heat mercury or mercury compounds, it should be done in a well-ventilated hood. Containers of mercury should be securely covered and spillage should be avoided. It is important therefore that mercury be handled with care. The danger increases at higher temperatures. Air saturated with mercury vapor at 20☌ contains a concentration that exceeds the toxicity limits. It acts as a cumulative poison and dangerous levels are readily attained in air. Mercury is a virulent poison and is readily absorbed through the respiratory tract, the gastrointestinal tract, or through unbroken skin. These products, held together with van der Waals' forces, correspond to HgNe, HgAr, HgKr, and HgXe. It has been found that an electrical discharge causes mercury vapor to combine with neon, argon, krypton, and xenon. It alloys with copper, tin, and zinc to form amalgams, or liquid alloys. Mercury is silvery white and slowly tarnishes in moist air. Mercury is the only elemental metal that is liquid at room temperature. The most important salts are mercury chloride (corrosive sublimate - a violent poison), mercurous chloride (calomel, occasionally still used in medicine), mercury fulminate, a detonator widely used in explosives, and mercuric sulfide (vermilion, a high-grade paint pigment). Mercury, chemical element, liquid metal of Group 12 of the periodic table. Its ease in amalgamating with gold is made use of in the recovery of gold from its ores. It easily forms alloys with many metals, such as gold, silver, and tin, which are called amalgams. It is a heavy, silvery-white metal a rather poor conductor of heat, as compared with other metals, and a fair conductor of electricity. The metal is obtained by heating cinnabar in a current of air and by condensing the vapor. The commercial unit for handling mercury is the "flask," which weighs 76 lb. The chief ore is cinnabar Spain and Italy produce about 50% of the world's supply of the metal. Mercury is the only common metal liquid at ordinary temperatures. Known to ancient Chinese and Hindus found in Egyptian tombs of 1500 B.C. Back to Elements List Mercury Atomic Number:įrom Greek hydoor.
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