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Manganese |
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Pronunciation | (MANG-gə-neez) |
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Appearance | silvery metallic |
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Standard atomic weight Ar, std(Mn) | 7001549380430000000♠54.938043(2)[1] |
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Manganese in the periodic cairt |
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Atomic nummer (Z) | 25 |
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Group | group 7 |
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Period | period 4 |
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Block | d-block |
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Element category | Transeetion metal |
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Electron confeeguration | [Ar] 3d5 4s2 |
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Electrons per shell | 2, 8, 13, 2 |
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Pheesical properties |
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Phase at STP | solit |
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Meltin pynt | 1519 K (1246 °C, 2275 °F) |
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Bylin pynt | 2334 K (2061 °C, 3742 °F) |
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Density (near r.t.) | 7.21 g/cm3 |
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when liquid (at m.p.) | 5.95 g/cm3 |
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Heat o fusion | 12.91 kJ/mol |
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Heat o vapourisation | 221 kJ/mol |
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Molar heat capacity | 26.32 J/(mol·K) |
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Vapour pressur
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
1228 |
1347 |
1493 |
1691 |
1955 |
2333 |
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Atomic properties |
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Oxidation states | −3, −2, −1, 0, +1, +2, +3, +4, +5, +6, +7 (dependin on the oxidation state, an acidic, basic, or amphoteric oxide) |
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Electronegativity | Pauling scale: 1.55 |
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Ionisation energies | |
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Atomic radius | empirical: 127 pm |
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Covalent radius | 139±5 (low spin), 161±8 (high spin) pm |
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Spectral lines o manganese |
Ither properties |
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Naitural occurrence | primordial |
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Creestal structur | body-centred cubic (bcc) |
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Speed o soond thin rod | 5150 m/s (at 20 °C) |
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Thermal expansion | 21.7 µm/(m·K) (at 25 °C) |
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Thermal conductivity | 7.81 W/(m·K) |
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Electrical resistivity | 1.44 µ Ω·m (at 20 °C) |
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Magnetic orderin | paramagnetic |
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Young's modulus | 198 GPa |
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Bulk modulus | 120 GPa |
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Mohs haurdness | 6.0 |
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Brinell haurdness | 196 MPa |
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CAS Nummer | 7439-96-5 |
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History |
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Diskivery | Torbern Olof Bergman (1770) |
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First isolation | Johann Gottlieb Gahn (1774) |
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Main isotopes o manganese |
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Isotope |
Abundance |
Hauf-life (t1/2) |
Decay mode |
Product |
52Mn |
syn |
5.591 d |
ε |
52Cr |
β+ |
52Cr |
γ |
- |
53Mn |
trace |
3.74×106 y |
ε |
53Cr |
54Mn |
syn |
312.3 d |
ε |
54Cr |
γ |
- |
55Mn |
100% |
stable |
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| references |