Ytterbium (Yb)
Element 70 · Lanthanide · atomic mass 173.05 u · f-block, period 6
Electron shells: 2, 8, 18, 32, 8, 2
Ytterbium's atomic clock transitions are even more precise than caesium's, making it a candidate to redefine the second. It also serves as a stress gauge under extreme pressure.
Ytterbium optical clocks would lose less than a second over the age of the universe.
- Atomic number
- 70
- Atomic mass
- 173.05 u
- Electron configuration
- [Xe] 6s² 4f¹⁴
- Group · period · block
- f-block · 6 · f
- Oxidation states
- +2, +3
- Electronegativity
- Not measured
- Melting point
- 819 °C
- Boiling point
- 1,196 °C
- Density
- 6.9 g/cm³
- State at 20 °C
- Solid
- Appearance
- Silvery, soft metal
- Discovered
- Jean Charles Galissard de Marignac, 1878
70 protons, and 70 electrons when neutral
IUPAC standard atomic weight
Shown in the strip below the table
What Ytterbium is used for
- Next-generation optical atomic clocks
- Fibre laser doping
- Stainless steel grain refinement
- Earthquake and stress sensors
Atomic structure of Ytterbium
A neutral ytterbium atom has 70 protons and 70 electrons. Its most common isotope carries about 103 neutrons, which is where the mass number 173 comes from. Change the neutron count and you have a different isotope of ytterbium; change the proton count and you have a different element entirely.
Those electrons fill shells from the inside out: 2, 8, 18, 32, 8, 2. In orbital notation that is [Xe] 6s² 4f¹⁴. As a f-block element its valence count is variable, which is why it can form compounds in several oxidation states.
3D electron orbitals
See where Ytterbium's electrons actually are — a cloud of 26,000 points sampled from the probability density |ψ|², not a cartoon of a lobe.
Where Ytterbium sits in the periodic table
Discovery and naming
Ytterbium was discovered by Jean Charles Galissard de Marignac in 1878. Its name comes from Ytterby, a Swedish village, which is also why its symbol (Yb) does not match its English name.
Keep exploring
Atomic weight from IUPAC/CIAAW; physical properties from PubChem (US National Library of Medicine). Values that have never been measured are shown as “not measured” rather than estimated.
Related Calculators
Frequently Asked Questions
What is the atomic mass of Ytterbium?
The standard atomic weight of Ytterbium is 173.05 u, as published by IUPAC's Commission on Isotopic Abundances and Atomic Weights.
How many protons, neutrons and electrons does Ytterbium have?
Ytterbium has 70 protons, because the atomic number is the proton count and that is what makes an atom Ytterbium at all. A neutral Ytterbium atom has the same number of electrons, 70. The neutron count varies by isotope; the most common one has about 103, since 173 − 70 = 103.
What is the electron configuration of Ytterbium?
The electron configuration of Ytterbium is [Xe] 6s² 4f¹⁴. Its electrons are arranged 2, 8, 18, 32, 8, 2 across 6 shells.
Is Ytterbium a metal?
Yes. Ytterbium is classified as a lanthanide, on the metallic side of the table.
What group and period is Ytterbium in?
Ytterbium sits in the f-block strip below the main table, in period 6, among the lanthanides. Elements in that strip are not given a group number in the standard 18-column layout.
What is the charge of Ytterbium?
Ytterbium most commonly forms a 3+ or 2+ ion. Like most transition metals it has several accessible oxidation states, so the charge depends on the compound.
What is the melting point of Ytterbium?
Ytterbium melts at 819 °C and boils at 1,196 °C. That puts it in the solids at everyday temperatures.
What is Ytterbium used for?
Next-generation optical atomic clocks, Fibre laser doping, Stainless steel grain refinement, Earthquake and stress sensors. Ytterbium's atomic clock transitions are even more precise than caesium's, making it a candidate to redefine the second.
Who discovered Ytterbium, and where does its name come from?
Ytterbium (Yb) was discovered by Jean Charles Galissard de Marignac in 1878. The name comes from Ytterby, a Swedish village.