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Platinum is used on Dental crowns.


Symbol Name Atomic Number Atomic Weight Group Number
Pt Platinum 78 195.08 10


Standard State: Solid at 298 K
Color: Grayish white

Ulloa discovered platinum in South America in 1735 and by Wood in 1741. The metal was used by pre-Columbian Indians.  Platinum occurs native, accompanied by small quantities of iridium, osmium, palladium, ruthenium, and rhodium, all belonging to the same group of metals.  The metal does not oxidize in air at any temperature, but is corroded by halogens, cyanides, sulfur, and caustic alkalis.  Platinum resistance wires are used for constructing high-temperature electric furnaces.  The metal is used for coating missile nose cones, jet engine fuel nozzles.  The metal , like palladium, absorbs large volumes, of hydrogen, retaining it at ordinary temperatures but giving it up at red heat.