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ELEMENT 043 · TRANSITION METAL

Technetium · Tc Technetium

has no stable isotope; certain radioactive isotopes are used for nuclear medicine tracers.

atomic number / Atomic number
43
atomic weight / Atomic mass
96.90636 u
Family/Group
7
Period · Block / Period · Block
5 · d
Category / Category
transition metal · Transition metal
State / State
solid state
Electron configuration
[Kr]5s2 4d5
Oxidation states / Oxidation states
+7, +6, +4
Electronegativity / Electronegativity
1.9(Pauling)
Density / Density
11 g/cm³
Melting point / Melting point
2430 K
Boiling point / Boiling point
4538 K
Atomic radius / Atomic radius
209 pm(van der Waals)
First ionization energy
7.28 eV
Discovery year / Discovery
1937

attribute description and data source

properties taken from PubChem periodic table snapshot (2026-10-04). Atomic weights may be reference values ​​or representative isotope masses and cannot be considered exact constants for all samples; density, phase transition points, and phase states depend on temperature, pressure, and allotropes. The solidification of helium requires pressure. Some properties of radioactive and superheavy elements are predicted values, and missing items are marked as not included. Please check the original source and experimental conditions for precise calculations.

PubChem · Technetiumoriginal information ↗

involves TechnetiumThe final phase of

current index collection 0strips. The reaction description is only used for knowledge query and material relationship understanding.

does not yet contain a reaction entry for this element; this does not mean that there are no known reactions for this element.