Mendeleev
Periodic table · chemistry · physics
Element story

Erbium

Atomic number 68 means that every Erbium nucleus contains 68 protons. That proton count is the element's identity: change it and you no longer have Erbium.

Start with the nucleus

Atomic number 68 means that every Erbium nucleus contains 68 protons. That proton count is the element's identity: change it and you no longer have Erbium.

Erbium (Er) is chemical element 68. It belongs to the lanthanoids, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

In practice, it turns up most often in fibre optics, lasers and special glasses.

See the atom

Conceptual visual: electron shells are a learning aid, not a literal picture of quantum orbitals.

What this number means

Atomic number 68 means that every Erbium nucleus contains 68 protons. That proton count is the element's identity: change it and you no longer have Erbium.

Keep exploring

→ Erbium · Atomic structure · Periodic trends

68ErErbium
Erbium · Er · Z = 68

Erbium (Er) is chemical element 68. It belongs to the lanthanoids, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

Understanding the element

Erbium (Er) is chemical element 68. It belongs to the lanthanoids, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

Where do we encounter it?

In practice, it turns up most often in fibre optics, lasers and special glasses.

What its position in the table tells us

Erbium sits in period 6 and the F block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.