Pure Metals and Minerals

Tantalum: [1] Melting point=2,996*C [2] very hard gray ductile metal [3] d 16.69 [4] very resistant to chemical attack [5] reacts with fluorine, chlorine, d2 on heating. At high temperatures absorbs several times its volume of hydrogen. combines with nitrogen and carbon. [6] platinum substitute Silicon: [1] silica is Quartz [2] poor conductor of low frequency electricity [3] d 25/4 2.33 [4] melting point: 1m410*C [5] attacked by HF or HNO4 + HF. Soluble in molten alkali metals. Burns in Fl and Chlorine Silver: [1] excellent conductor ofheat and low frequency electricity [2] melting point: 960.5*C/ Boiling Point: 2,000*C [3] d15 10.49 [4] inert to most acids, atmospheric oxygen. readily reacts wit dilute H2NO4 and hot concentrated H2SO4 [5] has been used to purify drinking water due to toxicity to most lower forms of life Aluminum: [1] non magnetic to lower frequency magnetism [2] d 2.70 [3] melting point: 660*C/ boilimg Point: 2,327*C Boron Carbide: [1] abrasive [2] hardness less than industrial diamonds but higher than silicon carbide [3] moh's hardness: 9.3 [4] melting point: 2,350*C/ boiling point: 3,500*C [5] black shiny colour Borazon: [1] boron nitride [2] hardest substance known [3] melting point: 3,000*C [amorphous modification] [4] resistant to chemical attack