ASCII PERIODIC TABLE OF THE ELEMENTS
Mn
Relative atomic mass: 54.938045 +- 0.000005
English: Manganese
French: Manganese
Croatian: Mangan
German: Mangan
Italian: Manganese
Spanish: Manganeso
Atomic number: 25
Group numbers: 7
Period: 4
Standard state (20 oC): solid
Discovery: 1774 Johan Gottlieb Gahn (SE)
Manganese was discovered by Johan Gottlieb Gahn (SE) in 1774. The origin of the name comes from the Latin word magnes meaning magnet, or magnesia nigri meaning black magnesia (MnO2). It is a hard, brittle, grey-white metal with a pinkish tinge. Impure forms are reactive and rust like iron in moist air. Manganese is most abundant ores are pyrolusite (MnO2), psilomelane [(Ba,H2O)2Mn5O10] and rhodochrosite (MnCO3). Pure metal is produced by mixing MnO2 with powered Al and ignited in a furnace. It's used in steel, batteries and ceramics. The steel in railroad tracks can contain as much as 1.2% manganese. It is crucial to the effectiveness of vitamin B1. The price of 99.9 % pure manganese pieces is 87.80 € for 1000 g.
Electronic configuration: [Ar] 3d5 4s2
Formal oxidation number: +2 +3 +4 +7
Atomic radius: 136.7 pm
Electronegativities: 1.55
Thermal conductivity: 7.82 W/(m K)
Electrical resistivity (20 oC): 144 microOhm cm
Melting point: 1246 oC
Boiling point: 2061 oC
Heat of fusion: 14.4 kJ/mol
Heat of vaporization: 220.5 kJ/mol
Heat of atomization: 279.37 kJ/mol
24Cr <= 25Mn => 26Fe
ASCII Periodic Table of the Elements
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6 Jan. 2020
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