Template:Infobox technetium

	child table, as reused in {IB-Tc} v; e; h;
Main isotopes of technetium
IT	95Tc
ε	97Mo
β−	99Ru

Technetium, ₄₃Tc
Technetium
Pronunciation	/tɛkˈniːʃ(i)əm/ (tek-NEE-sh(ee-)əm)
Appearance	shiny gray metal
Mass number	[97] (data not decisive)
Technetium in the periodic table
	molybdenum ← technetium → ruthenium
Atomic number (Z)	43
Group	group 7
Period	period 5
Block	d-block
Electron configuration	[Kr] 4d5 5s2
Electrons per shell	2, 8, 18, 13, 2
Physical properties
Phase at STP	solid
Melting point	2430 K (2157 °C, 3915 °F)
Boiling point	4538 K (4265 °C, 7709 °F)
Density (at 20° C)	98Tc: 11.359 g/cm3; 99Tc: 11.475 g/cm3
Heat of fusion	33.29 kJ/mol
Heat of vaporization	585.2 kJ/mol
Molar heat capacity	24.27 J/(mol·K)
Atomic properties
Oxidation states	−1, 0, +1,[citation needed] +2, +3, +4, +5, +6, +7 (a strongly acidic oxide)
Electronegativity	Pauling scale: 1.9
Ionization energies	1st: 686.9 kJ/mol ; 2nd: 1470 kJ/mol ; 3rd: 2850 kJ/mol ; ;
Atomic radius	empirical: 136 pm
Covalent radius	147±7 pm
Van der Waals radius	205 pm
	Spectral lines of technetium
Other properties
Natural occurrence	from decay
Crystal structure	hexagonal close-packed (hcp) (hP2)
Lattice constants	a = 274.12 pm; c = 439.90 pm (at 20 °C)
Thermal expansion	8.175×10−6/K (at 20 °C)
Thermal conductivity	50.6 W/(m⋅K)
Electrical resistivity	200 nΩ⋅m (at 20 °C)
Magnetic ordering	Paramagnetic
Molar magnetic susceptibility	+270.0×10−6 cm3/mol (298 K)
Speed of sound thin rod	16,200 m/s (at 20 °C)
CAS Number	7440-26-8
History
Prediction	Dmitri Mendeleev (1871)
Discovery and first isolation	Emilio Segrè and Carlo Perrier (1937)
Isotopes of technetium v; e;
IT	95Tc
ε	97Mo
β−	99Ru
	Category: Technetium; view; talk; edit; \| references

Tc · Technetium
Mo ← ibox Mo	^iso ₄₃Tc [e] IB-Tc [e] IBisos [e]	→ Ru ibox Ru
cat:Tc (6) cat:Tc-isotopes (41) Commons Wikidata:Q1054 Wiktionary
indexes by PT (page) v e

Data sets read by {{Infobox element}}
Name and identifiers	view edit
Symbol etymology (11 non-trivial)	view edit
Top image (caption, alt)	view edit
Pronunciation	view edit
Allotropes (overview)	view edit
Group (overview)	view edit
Period (overview)	view edit
Block (overview)	view edit
Natural occurrence	view edit
Phase at STP	view edit
Oxidation states	view edit
Spectral lines image	view edit
Electron configuration (cmt, ref)	view edit
Isotopes
Standard atomic weight	view edit
most stable isotope	view edit
Wikidata
Wikidata *	view edit
* Not used in {{Infobox element}} (2023-01-01) See also {{Index of data sets}} · Cat:data sets (12) · (this table: v )

References

^ ^1.0 ^1.1 ^1.2 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.
^ ^2.0 ^2.1 ^2.2 Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9.
^ Mattolat, C.; Gottwald, T.; Raeder, S.; Rothe, S.; Schwellnus, F.; Wendt, K.; Thörle-Pospiech, P.; Trautmann, N. (24 May 2010). "Determination of the first ionization potential of technetium". Physical Review A. 81: 052513. doi:10.1103/PhysRevA.81.052513.
^ Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.

^ The most stable isotope of technetium cannot be determined based on existing data due to overlapping measurement uncertainties for the half-lives of the two longest-lived isotopes. The half-life of ⁹⁷Tc with an uncertainty corresponding to one standard deviation is 4.21±0.16 million years, while that for ⁹⁸Tc is 4.2±0.3 million years; these measurements have overlapping confidence intervals.^[1]

References

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[NUBASE2020-1] 1.0 ^1.1 ^1.2 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.

[Arblaster_2018-3] 2.0 ^2.1 ^2.2 Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9.

[4] Mattolat, C.; Gottwald, T.; Raeder, S.; Rothe, S.; Schwellnus, F.; Wendt, K.; Thörle-Pospiech, P.; Trautmann, N. (24 May 2010). "Determination of the first ionization potential of technetium". Physical Review A. 81: 052513. doi:10.1103/PhysRevA.81.052513.

[5] Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.

[most_stable_isotope-2] The most stable isotope of technetium cannot be determined based on existing data due to overlapping measurement uncertainties for the half-lives of the two longest-lived isotopes. The half-life of ⁹⁷Tc with an uncertainty corresponding to one standard deviation is 4.21±0.16 million years, while that for ⁹⁸Tc is 4.2±0.3 million years; these measurements have overlapping confidence intervals.^[1]

[a]

[2]

[3]

[4]

[1]