Chemistry RPeriod 4(5A)
Name & Symbol: Platinum (Pt)
-Atomic Number: 78
-Atomic Mass: 195.084 amu
-Appearance: Shiny, smooth surface, silver like, solid.
Melting point (K): 2045
Boiling point (K): 4100
Valence electrons: (+1), +2, (+3), +4, +6
Atomic radius (pm): 139
1st Ionization energy (kJ/mol): 868.1
Natural Occurring Isotopes: Six stable isotopes of platinum occur in nature (190, 192, 194, 195, 196, 198). Information on three additional radioisotopes is available (191, 193, 197). Location on the periodic table: -Transition Metals section. -10th group/family.
History of element:
-It's difficult to assign credit for the discovery. Ulloa 1735 (in South America), Wood in 1741, Julius Scaliger in 1735 (Italy) all can make claims. Platinum was used in relatively pure form by the pre-Columbian Indians. -The first mention for Platinum is found in description of Italian humanist Julius Caesar Scaliger as mentioned a noble white metal found in Darien and Mexico. -Past uses: During the latter eighteenth century, platinum had some industrial uses. It was used to make durable laboratory instruments in Berlin in 1784. In France crucibles for glass production used it, a significant use still today. Platinum also began to impress jewelers and goldsmiths. Leading metal workers, such as Marc Janety, Royal Goldsmith to Louis XVI, and Pierre Chabaneu, of Spain, were using platinum to make expensive cutlery, watch-chains and coat buttons. Early in the 19th century, new refining techniques increased platinum’s availability. It was soon being used in gun parts, sophisticated batteries and fuel cells, the production of caustic chemicals (the first platinum sulfuric acid boiler weighed over 400 ounces) and the purification of hydrogen. -Present uses: Todays uses for Platinum are mainly for jewelry. The one use that hasn’t changed is that platinum is still used...