mol-1 Atomic: Oxidation States: 8, 7, 6, 4, 3, 2, 1, -2 Electronegativity: 2.3 (Pauling scale) Atomic Radius: 134 picometre Covalent Radius: 146 7 picometre Ionization Energies: 710.2 kJ.mol-1 (first), 1620 kJ.mol-1 (second), 2747 kJ.mol-1 (third) Ruthenium-palladium and ruthenium-platinum alloys are used in making electrical contacts for wear resistance. British Britannia (with a face value of 100 pounds). 2. Chinese Gold Panda (with face values of 500, 200, 100, 50, and 25 Yuan). 3. Swiss Helvetia Head (with face values of 100, 20, and 10 Swiss francs). 4. Austrian Vienna Philharmonic (with face values of 100, 50, 25, and 10 euros). Silver coins, like the minted coins circulated in the United States and other countries prior to 1965, were made of 90% silver and 10% copper. When alloyed with some of the other metals in the platinum group, such as iridium or platinum, osmium is used in certain applications where extreme hardness and durability are required. A couple examples of these are for electrical contacts and for tips of high quality fountain pens. Some of the properties osmium possesses are outlined below. Jewelry (sterling silver is used in making fine jewelry and watches). 2. Silverware (sterling silver is also used in making utensils, tableware and ornaments). 3. Photography (silver nitrate and silver halides are used in making films). 4. Electrical and electronic products (silver paints are used in making printed circuits; silver electrical contacts are used in making computer keyboards). Owning a gold certificate: A gold investor may opt to hold on to a gold certificate rather than store the physical gold bullion. The gold certificate allows the investor to buy and sell the security and do away with the many difficulties associated with the actual gold's transfer. Trading in Gold Exchange-Traded Funds (GETFs): Trading in GETFs is like trading shares in, say, the New York Stock Exchange or the London Stock Exchange. Still, precious metals have some safety issues attached to them: Rhenium: Since rhenium is used in very small amounts, its toxicity is virtually unknown. The hazardous property of rhenium halide, for example, may be attributed either to rhenium itself or to the other elements that make up the compound.