Lanthanum (La) — Element 57: Properties & Data | Aladdin Scientific
Lanthanum(La) — Element 57
Lanthanum (La) is a lanthanide with atomic number 57 and atomic mass 138.905. It has melting point 1191 K (918 °C), boiling point 3737 K (3464 °C), density 6.15 g/cm³. It sits in period 6 of the periodic table and was discovered in 1839.
Key facts
| Atomic mass | 138.9055 u |
|---|---|
| Electron configuration | [Xe]6s2 5d1 |
| Oxidation states | +3 |
| Electronegativity (Pauling) | 1.1 |
| Atomic radius (van der Waals) | 240 pm |
| Ionization energy | 5.577 eV |
| Electron affinity | 0.5 eV |
| Melting point | 1191 K |
| Boiling point | 3737 K |
| Density | 6.15 g/cm³ |
| Standard state | Solid |
| Year discovered | 1839 |
Frequently asked questions
What is the electron configuration of lanthanum?
The ground-state electron configuration of lanthanum is [Xe]6s2 5d1.
What group and period is lanthanum in?
Lanthanum (La) is in period 6 (lanthanide series) of the periodic table, classified as a lanthanide.
What is the melting point of lanthanum?
Lanthanum melts at 1191 K (918 °C).
What is the standard state of lanthanum?
Lanthanum is a solid at standard temperature and pressure.
Related elements
About this data: property values compiled from IUPAC Standard Atomic Weights (2021), the NIST Atomic Spectra Database, and PubChem. Curated by the Aladdin Scientific technical team. Last reviewed: .