Lanthanoid series

Definition

The lanthanoid series consists of 15 metallic elements with atomic numbers from 57 to 71, starting with lanthanum and ending with lutetium. These elements are known for their similar properties and are also referred to as rare earth elements.

5 Must Know Facts For Your Next Test

1. Lanthanoids have partially filled 4f orbitals.
2. They exhibit a phenomenon known as lanthanide contraction, where atomic and ionic sizes decrease with increasing atomic number.
3. Lanthanoids are typically trivalent in their compounds, meaning they most commonly form +3 oxidation states.
4. Despite being called rare earth elements, many lanthanoids are relatively abundant in the Earth's crust.
5. These metals often form brightly colored complexes and possess unique magnetic and optical properties.

Review Questions

Related terms

Transition Metals:

Elements found in groups 3-12 of the periodic table which have partially filled d orbitals.

Coordination Chemistry:

The study of compounds formed between metal ions and organic or inorganic ligands.

Actinoid Series: A series of elements from actinium (Ac) to lawrencium (Lr) characterized by filling of the 5f orbitals.