Chemistry Quick Facts
Google
 
 
Element Properties
   By Name
  By Atomic Number
  By Density
  Melting & Boiling Point
  Electron Configuration
  Radioactive Elements
  Noble & Precious Metals
Periodic Table
Groups
   Periodic Table
  Alkali Metals
  Alkaline Earth Metals
  Halogens
  Noble (Inert) Gases
  Rare Earth Elements
  Transition Metals
  Metalloids (Semimetals)
  Nonmetals
  Poor Metals
Materials
   Toxic Substances
  Semiconductor Materials
  Vitamins
  Amino Acids
Inventions
& Patents
Reference


Tantalum
Chemical Properties & Compounds



Symbol Atomic Number Atomic Weight Melting Point Boiling Point Phase Density Classification
Ta 73 180.94788 3017 °C 5458 °C Solid 16.69 g/cm3 Noble Metal


73 hafnium ← tantalum → tungsten
Nb
↑
Ta
↓
Db
General
Name, Symbol, Number tantalum, Ta, 73
Chemical series transition metals
Group, Period, Block 5, 6, d
Appearance gray blue
Standard atomic weight 180.94788(2)  g·mol−1
Electron configuration [Xe] 4f14 5d3 6s2
Electrons per shell 2, 8, 18, 32, 11, 2
Physical properties
Phase solid
Density (near r.t.) 16.69  g·cm−3
Liquid density at m.p. 15  g·cm−3
Melting point 3290 K
(3017 °C, 5463 °F)
Boiling point 5731 K
(5458 °C, 9856 °F)
Heat of fusion 36.57  kJ·mol−1
Heat of vaporization 732.8  kJ·mol−1
Heat capacity (25 °C) 25.36  J·mol−1·K−1
Vapor pressure
P(Pa) 1 10 100 1 k 10 k 100 k
at T(K) 3297 3597 3957 4395 4939 5634
Atomic properties
Crystal structure cubic body centered
Oxidation states 5, 4, 3 (mildly acidic oxide)
Electronegativity 1.5 (scale Pauling)
Ionization energies 1st: 761 kJ/mol
2nd: 1500 kJ/mol
Atomic radius 145  pm
Atomic radius (calc.) 200  pm
Covalent radius 138  pm
Miscellaneous
Magnetic ordering no data
Electrical resistivity (20 °C) 131 n Ω·m
Thermal conductivity (300 K) 57.5  W·m−1·K−1
Thermal expansion (25 °C) 6.3  µm·m−1·K−1
Speed of sound (thin rod) (20 °C) 3400 m/s
Young's modulus 186  GPa
Shear modulus 69  GPa
Bulk modulus 200  GPa
Poisson ratio 0.34
Mohs hardness 6.5
Vickers hardness 873  MPa
Brinell hardness 800  MPa
CAS registry number 7440-25-7
Selected isotopes
Main article: Isotopes of tantalum
iso NA half-life DM DE (MeV) DP
177Ta syn 56.56 h ε 1.166 177Hf
178Ta syn 2.36 h ε 1.910 178Hf
179Ta syn 1.82 a ε 0.110 179Hf
180Ta syn 8.125 h ε 0.854 180Hf
180Ta syn 8.125 h β- 0.708 180W
180mTa 0.012% >1.2×1015 y ε 0.929 180Hf
β- 0.783 180W
IT 0.075 180Ta
181Ta 99.988% Ta is stable with 108 neutrons
182Ta syn 114.43 d β- 1.814 182W
183Ta syn 5.1 d β- 1.070 183W
References
Tantalum Compounds

Source: Wikipedia article Tantalum


Privacy   Disclaimer   Contact   About    Site Map   Home

Last updated: October 2007

Copyright © 2006-2007 Patent-Invent.com