Technetium

Document v1 · published by Koskamo · updated 2026-10-04

Technetium (Tc) is chemical element 43, a transition metal in group 7, period 5 (PubChem).

Atomic number: 43
Symbol: Tc
Group: 7
Period: 5
Atomic mass: 96.90636 u
Electron configuration: [Kr]5s2 4d5
Electronegativity (Pauling scale): 1.9
Atomic radius (van der Waals): 209 pm
Ionization energy: 7.28 eV
Electron affinity: 0.55 eV
Oxidation states: +7, +6, +4
Standard state: Solid
Melting point: 2430 K
Boiling point: 4538 K
Density: 11 g/cm³
Chemical group: Transition metal
Year discovered: 1937

Source and provenance

Original source: pubchem.ncbi.nlm.nih.gov
Published on Koskamo by: Koskamo
Citation version: Document v1
Reuse: PubChem periodic table data (NIH/NLM, pubchem.ncbi.nlm.nih.gov/ptable); group and period from Jefferson Lab via PubChem

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Version history

Published by Koskamo2026-10-04
Version 1