Template:Infobox technetium

Technetium, 43Tc
Technetium
Pronunciation/tɛkˈnʃ(i)əm/ (tek-NEE-sh(ee-)əm)
Appearanceshiny gray metal
Mass number[97]
Technetium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Mn

Tc

Re
molybdenumtechnetiumruthenium
Atomic number (Z)43
Groupgroup 7
Periodperiod 5
Block  d-block
Electron configuration[Kr] 4d5 5s2
Electrons per shell2, 8, 18, 13, 2
Physical properties
Phase at STPsolid
Melting point2430 K ​(2157 °C, ​3915 °F)
Boiling point4538 K ​(4265 °C, ​7709 °F)
Density (near r.t.)11 g/cm3
Heat of fusion33.29 kJ/mol
Heat of vaporization585.2 kJ/mol
Molar heat capacity24.27 J/(mol·K)
Vapor pressure (extrapolated)
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2727 2998 3324 3726 4234 4894
Atomic properties
Oxidation states−3, −1, 0, +1,[1] +2, +3,[1] +4, +5, +6, +7 (a strongly acidic oxide)
ElectronegativityPauling scale: 1.9
Ionization energies
  • 1st: 702 kJ/mol
  • 2nd: 1470 kJ/mol
  • 3rd: 2850 kJ/mol
Atomic radiusempirical: 136 pm
Covalent radius147±7 pm
Van der Waals radius205 pm
Color lines in a spectral range
Spectral lines of technetium
Other properties
Natural occurrencefrom decay
Crystal structurehexagonal close-packed (hcp)
Hexagonal close packed crystal structure for technetium
Speed of sound thin rod16,200 m/s (at 20 °C)
Thermal expansion7.1 µm/(m⋅K)[2] (at r.t.)
Thermal conductivity50.6 W/(m⋅K)
Electrical resistivity200 nΩ⋅m (at 20 °C)
Magnetic orderingParamagnetic
Molar magnetic susceptibility+270.0×10−6 cm3/mol (298 K)[3]
CAS Number7440-26-8
History
PredictionDmitri Mendeleev (1871)
Discovery and first isolationEmilio Segrè and Carlo Perrier (1937)
Isotopes of technetium
Main isotopes[4] Decay
abun­dance half-life (t1/2) mode pro­duct
95mTc synth 61.96 d β+ 95Mo
IT 95Tc
96Tc synth 4.28 d ε 96Mo
γ
97Tc synth 4.21×106 y ε 97Mo
97mTc synth 91.1 d IT 97Tc
ε ...
98Tc synth 4.2×106 y β 98Ru
β+
99Tc trace 211.1×103 y β 99Ru
99mTc synth 6.01 h IT 99Tc
β
 Category: Technetium
| references
Data sets read by {{Infobox element}}
Name and identifiers
Symbol etymology (11 non-trivial)
Top image (caption, alt)
Pronunciation
Allotropes (overview)
Group (overview)
Period (overview)
Block (overview)
Natural occurrence
Phase at STP
Oxidation states
Spectral lines image
Electron configuration (cmt, ref)
Isotopes
Standard atomic weight
  most stable isotope
Wikidata
Wikidata *
* Not used in {{Infobox element}} (2023-01-01)
See also {{Index of data sets}} · Cat:data sets (11) · (this table: )

References

  1. 1.0 1.1 "Technetium: technetium(III) iodide compound data". OpenMOPAC.net. Retrieved 2007-12-10.
  2. Cverna, Fran (2002). "Ch. 2 Thermal Expansion". ASM Ready Reference: Thermal properties of metals (PDF). ASM International. ISBN 978-0-87170-768-0.
  3. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
  4. Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.