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Erbium (Er) – Element 68 of the periodic table

Erbium (symbol Er) is element number 68 of the periodic table and belongs to the “Lanthanide” category. Its atomic mass is about 167.26, and its phase under standard conditions is Solid. This element sits in period 6 and the f-block (Lanthanides) of the periodic table, and its electrons are arranged in shells of 2, 8, 18, 30, 8, 2. The short electron configuration of Erbium is [Xe] 4f¹² 6s². Known uses of Erbium include Fiber optics, Medical lasers and Colored glass.

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Properties of Erbium

Atomic number
68
Chemical symbol
Er
Atomic mass
167.26
Category
Lanthanide
Period
6
Block
f
Phase
Solid
Protons
68
Electrons
68
Neutrons (approx.)
99
Electron shells
2, 8, 18, 30, 8, 2
Outer-shell electrons
2
Discovered
Carl Gustaf Mosander (1843)

Electron configuration of Erbium

The electron configuration of Erbium (Er), with 68 electrons, is shown below. The last shell (shell 6) is highlighted:

Full configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹² 5s² 5p⁶ 6s²
Short configuration
[Xe] 4f¹² 6s²
Last shell
6s²

What is electron configuration and how is it written?

Electron shells of Erbium

Distribution of 68 electrons of Erbium across shells K to P:

  1. K2
  2. L8
  3. M18
  4. N30
  5. O8
  6. P2

What is a lanthanide?

The lanthanides are the 15 elements from lanthanum to lutetium, part of the f-block, with very similar chemical properties; they are often grouped among the “rare earths”.

Uses of Erbium

Frequently asked questions about Erbium

What is the atomic number of Erbium?

The atomic number of Erbium (Er) is 68; that is, every atom of it has 68 protons.

What is the electron configuration of Erbium?

The electron configuration of Erbium (Er) is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹² 5s² 5p⁶ 6s²; in short form it is [Xe] 4f¹² 6s², and its last shell is 6s².

What is the chemical symbol of Erbium?

The chemical symbol of Erbium is Er.

Where is Erbium located in the periodic table?

Erbium is located in period 6 and the f-block (Lanthanides) and belongs to the “Lanthanide” category.

What is the atomic mass of Erbium?

The atomic mass of Erbium is about 167.26 (atomic mass units).

What is the phase of Erbium under normal conditions?

The phase of Erbium under standard conditions is Solid.

What are the uses of Erbium?

Uses of Erbium include Fiber optics, Medical lasers and Colored glass.

Who discovered Erbium?

Erbium was discovered by Carl Gustaf Mosander in 1843.

Elements in the same category as Erbium (Lanthanide)

Lanthanum (La)Cerium (Ce)Praseodymium (Pr)Neodymium (Nd)Promethium (Pm)Samarium (Sm)Europium (Eu)Gadolinium (Gd)Terbium (Tb)Dysprosium (Dy)Holmium (Ho)Thulium (Tm)Ytterbium (Yb)Lutetium (Lu)

See all Lanthanides