Technetium

Identity

Atomic number

43

Symbol

Tc

Canonical name

Technetium

Category

transition metal

Group

7

Period

5

Block

d

Former names

masurium, eka-manganèse

Properties

These quantities come from the Periodic Table JSON compilation. They have not yet been checked, one by one, against CIAAW atomic weights or NIST measurements. A value marked estimated is not a measurement.

Atomic mass

[98] No standard atomic weight. The number shown is the conventional mass number used in tables, not a measured mass in u.

Electron configuration

[Kr] 4d5 5s2

Electrons per shell

2, 8, 18, 13, 2

Standard state

solid

Density

11 g/cm³

Melting point

2,430 K

Boiling point

4,538 K

Electronegativity

1.9 Pauling

First ionization energy

702 kJ/mol

Electron affinity

53 kJ/mol

Notable isotopes

This summary is not an inventory of every isotope.

Conventional mass number: 98

History

See the element timeline

Etymology

Theme

property

Language

grec

Root

tekhnetos

Meaning

artificial

Scientists

• Walter Noddack
• Ida Noddack
• Otto Berg
• Carlo Perrier
• Emilio Segrè

Places and institutions

• University of Palermo
• Berkeley Radiation Laboratory, later Lawrence Berkeley National Laboratory

• Berlin — historical setting : Prussia, then Germany — present country : Germany
• Palermo — historical setting : Italy — present country : Italy

See also

• 25 Manganese (Mn)
• 75 Rhenium (Re)
• 85 Astatine (At)
• 107 Bohrium (Bh)

Sources

• IUPAC, Periodic Table of the Elements
• Bowserinator, Periodic Table JSON. Compilation secondaire d’où viennent les grandeurs physiques importées (masse, densité, températures, énergies). Elles ne sont pas revérifiées une à une auprès du NIST ou de la CIAAW.
• John Emsley, Nature’s Building Blocks: An A–Z Guide to the Elements