History Name is from the Greek word iodes, meaning violet or purple. Discovered by Bernard Courtois in 1811. Saltpeter (used to make gunpowder) was in great demand during the Napoleonic wars. Saltpeter produced from niter beds, require sodium carbonate an extract of the seaweed found on the coast of Normandy. To get the sodium carbonate the seaweed is burned. Normally the waste is disposed of by adding sulfuric acid. One day Bernard Courtois added more sulfuric acid then normal and a cloud of purple vapors rose up.
Properties Melting point- 386.7 K Boiling point- 457.5 K Density g/cc- 4.93 Less Hygroscopic- easy to work with in film. At room temperature Iodine is a gas At 20 C it is a solid. Metallic gray as a solid.
Properties There are 23 known Isotopes found in nature and only one is stable I- 127. The radioisotope I- 131 with a half-life 8 days has been used to treat thyroid disorders.
Availability Commercially Iodine is mined in Chile and extracted from iodine-rich brines notably from the oilfeilds in U.S. and Japan. Iodides are found in seawater and seaweed which absorb the compound. Pure Iodine cost $8.3 per 100g
Uses Iodine is essential for a proper diet. But is only good for your body in very small portions. You still must be carful when handling vapor is irritating to eyes and skin contact can cause lesions on the skin. KI is used to make film Used as a disinfectant in many forms
Fun Facts Abundance in seawater is estimated to be even less then .0003 parts per million. Least active halogen Heaviest element commonly used by living organisms. Helps with the rate of physical and mental development.
Bibliography Iodinefacts Anne Marie Helmenstine PHD 2011 New York Time company Http://chemistry.about.com/od/elementfacts/a/iodine.htm Iodine Chemicool Periodictable Chemcool.com 2011 Http://www.chemicool.com/elements/iodine.html Los Alumos National laboratory (2001)