Atoms of the same element are identical. The atoms of the one element are different from those of any other element. 3. Atoms of different elements can physically mix together or can chemically combine in simple whole-number ratios to form compounds.
iridium (symbol Ir) Silver-white, metallic element discovered in 1804 by the English chemist Smithson Tennant. A platinum-type metal, iridium is hard and brittle and the most corrosion-resistant metal. very rare element (0.0001 ppm of Earth 's crust), iridium is found in the naturally occurring alloys osmiridium (approximately 50% iridium) and iridiosmium (approximately 70% iridium) in Alaska and South Africa. It is obtained by igniting ammonium chloroiridate, (NH 4) 3 IrCl 6, in hydrogen atmosphere.
The reserves of iridium have not been estimated. This element is highly flammable and if it comes in contact with the eyes, it may cause irritation. Standard industrial handling poses low hazard when it comes to skin contact, but ingestion of iridium may cause irritation. It is, however, a low ingestion hazard.n its pure form, the element is very hard to machine and very brittle. The main application of iridium is as a hardening agent of platinum. High temperature equipment such as crucibles is made from platinum-iridium alloys.