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Name, Symbol, Number | Neodymium, Nd, 60 | ||||||||||||||||||||||||||||||||||||||||||||||||
Chemical series | Lanthanides | ||||||||||||||||||||||||||||||||||||||||||||||||
Group, Period, Block | _ , 6 , f | ||||||||||||||||||||||||||||||||||||||||||||||||
Density, Hardness | 6800 kg/m3, no data | ||||||||||||||||||||||||||||||||||||||||||||||||
Appearance | silvery white, yellowish tinge | ||||||||||||||||||||||||||||||||||||||||||||||||
Atomic properties | |||||||||||||||||||||||||||||||||||||||||||||||||
Atomic weight | 144.24(3) amu | ||||||||||||||||||||||||||||||||||||||||||||||||
Atomic radius (calc.) | 185 (206) pm | ||||||||||||||||||||||||||||||||||||||||||||||||
Covalent radius | no data | ||||||||||||||||||||||||||||||||||||||||||||||||
van der Waals radius | no data | ||||||||||||||||||||||||||||||||||||||||||||||||
Electron configuration | [Xe]4f4f46s² | ||||||||||||||||||||||||||||||||||||||||||||||||
e- 's per energy level | 2, 8, 18, 22, 8, 2 | ||||||||||||||||||||||||||||||||||||||||||||||||
Oxidation states (Oxide) | 3 (mildly basic) | ||||||||||||||||||||||||||||||||||||||||||||||||
Crystal structure | Hexagonal | ||||||||||||||||||||||||||||||||||||||||||||||||
Physical properties | |||||||||||||||||||||||||||||||||||||||||||||||||
State of matter | solid (__) | ||||||||||||||||||||||||||||||||||||||||||||||||
Melting point | 1297 K (1875 °F) | ||||||||||||||||||||||||||||||||||||||||||||||||
Boiling point | 3373 K (5612 °F) | ||||||||||||||||||||||||||||||||||||||||||||||||
Molar volume | 20.59 ×1010-3 m3/mol | ||||||||||||||||||||||||||||||||||||||||||||||||
Heat of vaporization | 273 kJ/mol | ||||||||||||||||||||||||||||||||||||||||||||||||
Heat of fusion | 7.14 kJ/mol | ||||||||||||||||||||||||||||||||||||||||||||||||
Vapor pressure | 6.03E-3 Pa at 2890 K | ||||||||||||||||||||||||||||||||||||||||||||||||
Velocity of sound | 2330 m/s at 293.15 K | ||||||||||||||||||||||||||||||||||||||||||||||||
Miscellaneous | |||||||||||||||||||||||||||||||||||||||||||||||||
Electronegativity | 1.14 (Pauling scale) | ||||||||||||||||||||||||||||||||||||||||||||||||
Specific heat capacity | 190 J/(kg*K) | ||||||||||||||||||||||||||||||||||||||||||||||||
Electrical conductivity | 1.57 106/m ohm | ||||||||||||||||||||||||||||||||||||||||||||||||
Thermal conductivity | 16.5 W/(m*K) | ||||||||||||||||||||||||||||||||||||||||||||||||
1st ionization potential | 533.1 kJ/mol | ||||||||||||||||||||||||||||||||||||||||||||||||
2nd ionization potential | 1040 kJ/mol | ||||||||||||||||||||||||||||||||||||||||||||||||
3rd ionization potential | 2130 kJ/mol | ||||||||||||||||||||||||||||||||||||||||||||||||
4th ionization potential | 3900 kJ/mol | ||||||||||||||||||||||||||||||||||||||||||||||||
Most stable isotopes | |||||||||||||||||||||||||||||||||||||||||||||||||
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SI units & STP are used except where noted. |
Neodymium is a chemical element in the periodic table that has the symbol Nd and atomic number 60.
Table of contents |
2 Applications 3 History 4 Biological role 5 Occurrence 6 Compounds 7 Isotopes 8 Precautions 9 External links |
Neodymium, a rare earth metal, is present in misch metal to the extent of about 18%. The metal has a bright silvery metallic luster; however, being one of the more reactive rare-earth metals, Neodymium quickly tarnishes in air, forming an oxide that spalls off and exposes the metal to further oxidation.
Uses of Neodymium include:
Neodymium was discovered by Baron Carl F. Auer von Welsbach, an austrian chemist, in Vienna in 1885. He separated neodymium, as well as the element Praseodymium, from a material known as didymium; however, it was not isolated in relatively pure form until 1925. The name Neodymium is derived from the greek words neos, new, and didymos, twin.
Today, Neodymium is primarily obtained from through an ion exchange process of monazite sand ((Ce,La,Th,Nd,Y)PO4), a material rich in rare earth elements, and through electrolysis of its halide salts.
Neodymium has no known biological role.
Neodymium is never found in nature as the free element; rather, it occurs in ores such as monazite sand ((Ce,La,Th,Nd,Y)PO4) and bastnosite ((Ce,La,Th,Nd,Y)(CO3)F) that contain small amounts of all the rare earth metals. Neodymium can also be found in Misch metal; it is difficult to separate from other rare earth elements.
Neodymium compounds include:
Naturally occurring Neodymium is composed of 5 stable isotopes, 142-Nd, 143-Nd, 145-Nd, 146-Nd and 148-Nd, with 142-Nd being the most abundant (27.2% natural abundance), and 2 radioisotopes, 144-Nd and 150-Nd. 31 radioisotopes have been characterized, with the most stable being 150-Nd with a half-life of 1.1E19 years, 144-Nd with a half-life of 2.29E15 years, and 147-Nd with a half-life of 10.98 days. All of the remaining radioactive isotopes have half-lifes that are less than 3.38 days, and the majority of these have half lifes that are less than 71 seconds. This element also has 4 meta states with the most stable being 139m-Nd (t½ 5.5 hours), 135m-Nd (t½ 5.5 minutes) and 141m-Nd (t½ 62.0 seconds).
The primary decay mode before the most abundant stable isotope, 142-Nd, is electron capture and the primary mode after is beta minus decay. The primary decay products before 142-Nd are element Pr (Praseodymium) isotopes and the primary products after are element Pm (Lead) isotopes. Notable characteristics
Applications
History
Biological role
Occurrence
Compounds
Isotopes