General: Chemical Symbol: Rh Atomic Number: 45 Category (as an element): Transition Metal Group/ Period/ Block (in the Periodic Table): 9/ 5/ d Atomic Weight: 102.90550 g.mol-1 Electron Configuration: [Kr] 4d8 5s1 Physical: Density (near room temperature): 12.41 g.cm-3 Liquid Density (at melting point): 10.7 g. In terms of mass abundance, expressed in parts per billion (ppb), here's how the nine precious metals are ranked (rare to rarest): 9th: silver (75 ppb); 8th: palladium (15 ppb); 7th: gold (4 ppb); 6th: osmium (1.5 ppb); 5th to 3rd: iridium, rhodium, and ruthenium (1 ppb); 2nd: rhenium (0.7 ppb); and 1st: platinum (0.003 ppb). It is the third element (after tungsten and carbon) with the highest melting point and the fourth densest (after platinum, iridium, and osmium). Commercially, rhenium is traded in powder form. Its principal application is in the making of certain parts of jet engines. Here, the metal is added to high-temperature nickel-based superalloys. mol-1 Electron Configuration: [Kr] 4d7 5s1 Physical: Density (near room temperature): 12.45 g.cm-3 Liquid Density (at melting point): 10.65 g.cm-3 Melting Point: 2334 C, 4233 F, 2607.4 K Boiling Point: 4150 C, 7502 F, 4423 K Heat of Fusion: 38.59 kJ.mol-1 Heat of Vaporization: 591.6 kJ.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. Throughout history, gold has served as a measure of value and a symbol of wealth. It is one of the coinage metals (along with silver and copper). It is used, customarily and legally, as a means of payment or a medium of exchange. Gram and troy weight are the units of measurement used for gold. To indicate the amount of gold present in, say, a piece of jewelry, the term "carat" is used. 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.