Platinum

Name: Platinum
Symbol: Pt
Atomic Number: 78
Atomic Weight: 195.084
Melting Point: 2041.55 K (1768.4°C or 3215.1°F)
Boiling Point: 4098 K (3825°C or 6917°F)
Density: 21.46 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 6
Group Number: 10
Group Name: none

The platinum group metals (PGMs) are comprised of six elements that include iridium, osmium, palladium, platinum, rhodium, and ruthenium.

Naturally occurring platinum and platinum-rich alloys have been known for a long time, and the word "platinum" was derived from the Spanish word “platina" which means silver. When the Spaniards first encountered platinum, they regarded it as an unwanted impurity in the silver they were mining.

Platinum occurs as a free element, usually mixed with other elements including gold, nickel, copper, palladium, ruthenium, rhodium, iridium and osmium. Platinum is a soft, dense, ductile metal that is very resistant to corrosion used to make jewellery, wire, electrical contacts and laboratory vessels. Platinum is used to coat missile nose cones, jet engine fuel nozzles and other devices that must operate reliably for long periods of time at high temperatures. Platinum resistance wires are used in high temperature electric furnaces. Platinum anodes are used in cathode protection systems to prevent ships, pipelines and steel piers from corroding in salt water.

Platinum is also used in a device called a catalytic converter, a device found in the exhaust systems of most modern cars. Catalytic converters combine carbon monoxide (CO) and unburned fuel from a car's exhaust with oxygen from the air, forming carbon dioxide (CO2) and water vapour (H2O). Platinum is also used as a catalyst in the production of sulfuric acid (H2SO4) and in the cracking of petroleum products. Fuel cells, devices that combine hydrogen and oxygen to produce electricity and water, also use platinum as a catalyst.