Erbium (Er)
Lanthanide · f-block · period 6
Soft, silvery metal; its compounds are a distinctive rose-pink.
Erbium (symbol Er) is chemical element number 68, a lanthanide in the lanthanide series (f-block), period 6 of the periodic table. Its standard atomic weight is 167.26 and its electron configuration is [Xe] 4f12 6s2. At room temperature it is a solid. Another of the four elements named after Ytterby.
Properties
| Atomic number | 68 |
|---|---|
| Atomic mass | 167.26 |
| Category | Lanthanide |
| Block | f-block |
| Group · Period | f-block series · 6 |
| Electron configuration | [Xe] 4f12 6s2 |
| Electrons per shell | 2, 8, 18, 30, 8, 2 |
| State at 25 °C | solid |
| Melting point | 1802 K |
| Boiling point | 3141 K |
| Density | 9.07 g/cm³ |
| Electronegativity (Pauling) | 1.24 |
| Radioactive | No |
| Origin | primordial |
| Discovered | 1843 · Carl Gustaf Mosander |
Key facts about Erbium
- Another of the four elements named after Ytterby.
- Erbium-doped fibres amplify the light in undersea internet cables, keeping the signal strong across oceans.
- Gives sunglasses and jewellery glass a soft pink tint.
- Erbium lasers are used in gentle skin resurfacing.
What Erbium is used for
Optical-fibre amplifiers for the internet, pink glass and glazes, dermatology and dental lasers, neutron absorbers.
Where it sits in the periodic table
Erbium is in the lanthanide series, period 6, of the f-block. Its electron configuration [Xe] 4f12 6s2 means its outermost shell holds 2 electrons, which is what places it here and explains much of its chemistry. See Erbium on the interactive table →
Erbium — frequently asked questions
What is Erbium used for?
Optical-fibre amplifiers for the internet, pink glass and glazes, dermatology and dental lasers, neutron absorbers.
Is Erbium radioactive?
No. Erbium has at least one stable isotope and is not radioactive.
What is the electron configuration of Erbium?
Erbium has the electron configuration [Xe] 4f12 6s2, which is 2, 8, 18, 30, 8, 2 electrons per shell.
What group and period is Erbium in?
Erbium is in the lanthanide series (f-block), period 6, in the f-block. Its outer shell holds 2 electrons.
Who discovered Erbium?
Erbium was discovered in 1843 by Carl Gustaf Mosander.