platinum

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platinum (symbol Pt) Lustrous, silver-white metal, the first of the six metallic transition elements. Platinum was used for decorations by pre-Columbian South Americans. It was discovered in 1557 in Central America by the Italian-born French scientist Julius Scaliger (1484–1558) with the Spanish conquistadors and named ‘little silver’ in Spanish (platina). it is chiefly found in certain ores of nickel. Malleable and ductile, it is used in jewellery, dentistry, electrical-resistance wire, magnets, thermocouples, surgical tools, electrodes and other laboratory apparatus, and as a catalyst in catalytic converters for car exhausts. It is chemically unreactive and resists tarnishing and corrosion. Properties: at.no. 78; r.a.m. 195.09; r.d. 21.45; m.p. 1772°C (3222°F); b.p. 3800°C (6872°F); most common isotope Pt195 (33.8%).

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