Periodic table / Lanthanoids

70Ytterbium

Ytterbium is a lanthanoid in period 6, in the lanthanoid series. At 25 °C it is a solid.

Yb
Shells: 2, 8, 18, 32, 8, 2. A simple picture: electrons do not move in circles.
Symbol
Yb
Atomic number
70 protons in the nucleus
Standard atomic weight
173.05 ± 0.02Some geological samples have an unusual isotope mix, so their atomic weight can fall outside this range.
Electron configuration
[Xe] 4f14 6s2
Electrons in each shell
2, 8, 18, 32, 8, 2
Group, period, block
–, 6, f
Family
Lanthanoids
State at 25 °C
solid
Electronegativity
no value
First ionisation energy
603.4 kJ/mol (6.25416 eV)
Where these numbers come from

Atomic weight: IUPAC CIAAW, abridged standard atomic weights 2024. Electron configuration and ionisation energy: NIST Atomic Spectra Database. Family, state and electronegativity: PubChem. See Sources. Melting points, boiling points and densities are left out for now: published values differ between sources, and we will add them once each has been checked.