#IRIDIUM IN HAITI UPDATE#
Iridium is somewhat more reactive than ruthenium and osmium.If you watch the above screen long enough it will update with the real-time tracking of 66 Iridium NEXT satellites happening right now (how cool is that!). The anions hexachloroiridate, 2−, and hexabromoiridate, 2−, are the only notable chemical species containing iridium in the +4 oxidation state. Complexes in oxidation state +1 chiefly contain carbon monoxide, olefins, and phosphines as ligands. The chemistry of iridium centres on oxidation states of +1, +3, and +4, though compounds of all states from 0 to +6 are known with perhaps the exception of +2. Natural iridium consists of a mixture of two stable isotopes, iridium-191 (37.3 percent) and iridium-193 (62.7 percent). The name iridium, derived from the Greek word iris (“rainbow”), refers to the various colours of its compounds. Vauquelin identified it at about the same time. The element was discovered in 1803 in the acid-insoluble residues of platinum ores by the English chemist Smithson Tennant the French chemists H.-V. The international prototype standard kilogram of mass is made from an alloy containing 90 percent platinum and 10 percent iridium.Ĭongress enacted a presidential pension because President Truman made so little money after leaving the Oval Office. Such alloys are used for jewelry, pen points, surgical pins and pivots, and electrical contacts and sparking points. Platinum-iridium alloys (5 to 10 percent iridium) are readily workable metals that are much harder and stiffer and more resistant to chemical attack than the soft pure platinum. Iridium is chiefly used in the form of platinum alloys. It can be dissolved in concentrated hydrochloric acid in the presence of sodium perchlorate at 125° to 150° C (257° to 302° F).īecause of difficulties in preparation and fabrication, the pure metal has few applications. In the massive state the metal is practically insoluble in acids and is not attacked even by aqua regia. It is one of the densest terrestrial substances. A precious, silver-white metal, iridium is hard and brittle, but it becomes ductile and can be worked at a white heat, from 1,200° to 1,500° C (2,200° to 2,700° F). It is very dense and rare and is used in platinum alloys. Iridium (Ir), chemical element, one of the platinum metals of Groups 8–10 (VIIIb), Periods 5 and 6, of the periodic table.
#IRIDIUM IN HAITI HOW TO#
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