43 Tc 98

Technetium

transition metal

Properties

Atomic number
43
Atomic mass
98 u
Category
transition metal
Group
7
Period
5
Block
d-block
State (room temp)
Solid
Outer-shell electrons
2
Electronegativity
1.9 (Pauling)
Density
11 g/cm³
Melting point
2156.85 °C
Boiling point
4264.85 °C

Electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d⁵

Noble-gas shorthand: [Kr] 4d⁵ 5s²

Electrons per shell: 2, 8, 18, 13, 2, which is 2 in the outermost shell.

Related: electron configuration, the Bohr model, valence electrons.

Tc
Bohr model; outer-shell electrons in blue

About Technetium

Technetium (/tɛkˈniːʃiəm/) is a chemical element with symbol Tc and atomic number 43. It is the element with the lowest atomic number in the periodic table that has no stable isotopes:every form of it is radioactive. Nearly all technetium is produced synthetically, and only minute amounts are found in nature.

Technetium: frequently asked questions

What is Technetium?
Technetium (Tc) is the chemical element with atomic number 43. It is a metal: specifically a transition metal.
What is the atomic number of Technetium?
Technetium's atomic number is 43, which means every Technetium atom has 43 protons in its nucleus.
What is the electron configuration of Technetium?
The electron configuration of Technetium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d5 (noble-gas shorthand: [Kr] 4d5 5s2). Its electrons are arranged in shells of 2, 8, 18, 13, 2, with 2 in the outermost shell.
Is Technetium a metal or a nonmetal?
Technetium is a metal: specifically a transition metal.
What group and period is Technetium in?
Technetium is in group 7 and period 5 of the periodic table.
Is Technetium a solid, liquid, or gas?
At room temperature, Technetium is a solid.

Position in the periodic table

Open the interactive periodic table →

Data compiled from Wikipedia, PubChem, and IUPAC. Source.