Molybdenum is a metallic element with a silver white color, atomic number 42, atomic weight 95.95 and density 10.2. Molybdenum plays an important role in alloys it creates with steel due to its strong carbide forming property. Due to its structure very similar to the soft black mineral molybdenite graphite, it was assumed to be a lead ore until 1778 before Carl Scheele showed it to be neither lead nor graphite, although he could not determine exactly what it was when analyzing it. Swedish chemist Peter Jacob separated molybdenum into metal in Hjelm in 1782 and named it after the Greek word molybdos, meaning "like lead".
Molybdenum can also be obtained directly by mining and as a byproduct during copper mining. Molybdenum is found in its ores in amounts ranging from 0.01% to 0.5%. About half of the world's molybdenum mining is done in the USA. Molybdenum, which is similar to chromium and wolfram in terms of chemical properties; It has superior properties such as high melting and boiling point, high heat resistance, high thermal conductivity and low thermal expansion. Molybdenum melts at 2623 ° C. With this feature, it takes the sixth place among metals. Molybdenum boiling at 4639 ° C is not affected by air in cold, oxidized in incandescent state, affected by nitric and sulfuric acids, decomposes water vapor at high temperatures. The density of molybdenum is 10.28 gr / cm3. Molybdenum is a transition metal with an electronegativity of 2.16 on the Pauling scale. Does not react visibly with oxygen or water at room temperature. Weak oxidation of molybdenum begins at 300 ° C; Bulk oxidation occurs at temperatures above 600 ° C, resulting in molybdenum trioxide. Although the Mo3 + cation is known under carefully controlled conditions, molybdenum, like many heavy transition metals, has little tendency to form a cation in an aqueous solution. Molybdenum is a versatile and price-influencing alloying material used in special steels, pig irons, nickel, cobalt and titanium-based alloys. Approximately 2/3 of the molybdenum compounds are used as molybdic oxide, 20% as ferromolybdenum, and the rest in the form of ammonium molybdate, calcium molybdate and sodium molybdate.
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