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Neodymium |
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Pronunciation | (NEE-oh-DIM-ee-əm) |
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Appearance | silvery white |
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Standard atomic weight Ar, std(Nd) | 7002144242000000000♠144.242(3)[1] |
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Neodymium in the periodic cairt |
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– ↑ Nd ↓ U |
praseodymium ← neodymium → promethium |
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Atomic nummer (Z) | 60 |
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Group | group n/a |
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Period | period 6 |
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Block | f-block |
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Element category | Lanthanide |
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Electron confeeguration | [Xe] 4f4 6s2 |
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Electrons per shell | 2, 8, 18, 22, 8, 2 |
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Pheesical properties |
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Phase at STP | solid |
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Meltin pynt | 1297 K (1024 °C, 1875 °F) |
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Bylin pynt | 3347 K (3074 °C, 5565 °F) |
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Density (near r.t.) | 7.01 g/cm3 |
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when liquid (at m.p.) | 6.89 g/cm3 |
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Heat o fusion | 7.14 kJ/mol |
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Heat o vapourisation | 289 kJ/mol |
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Molar heat capacity | 27.45 J/(mol·K) |
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Vapour pressur
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
1595 |
1774 |
1998 |
(2296) |
(2715) |
(3336) |
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Atomic properties |
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Oxidation states | 0,[2] +2, +3, +4 (a mildly basic oxide) |
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Electronegativity | Pauling scale: 1.14 |
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Ionisation energies | - 1st: 533.1 kJ/mol
- 2nd: 1040 kJ/mol
- 3rd: 2130 kJ/mol
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Atomic radius | empirical: 181 pm |
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Covalent radius | 201±6 pm |
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Spectral lines o neodymium |
Ither properties |
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Naitural occurrence | primordial |
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Creestal structur | dooble hexagonal close packed |
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Speed o soond thin rod | 2330 m/s (at 20 °C) |
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Thermal expansion | α, poly: 9.6 µm/(m·K) (at r.t.) |
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Thermal conductivity | 16.5 W/(m·K) |
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Electrical resistivity | α, poly: 643 nΩ·m |
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Magnetic orderin | paramagnetic, antiferromagnetic ablo 20 K[3] |
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Magnetic susceptibility | +5628.0·10−6 cm3/mol (287.7 K)[4] |
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Young's modulus | α form: 41.4 GPa |
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Shear modulus | α form: 16.3 GPa |
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Bulk modulus | α form: 31.8 GPa |
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Poisson ratio | α form: 0.281 |
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Vickers haurdness | 345–745 MPa |
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Brinell haurdness | 265–700 MPa |
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CAS Nummer | 7440-00-8 |
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History |
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Diskivery | Carl Auer von Welsbach (1885) |
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Main isotopes o neodymium |
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Isotope |
Abundance |
Hauf-life (t1/2) |
Decay mode |
Product |
142Nd |
27.2% |
stable |
143Nd |
12.2% |
stable |
144Nd |
23.8% |
2.29×1015 y |
α |
140Ce |
145Nd |
8.3% |
stable |
146Nd |
17.2% |
stable |
148Nd |
5.8% |
stable |
150Nd |
5.6% |
6.7×1018 y |
β−β− |
150Sm |
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| references |