La
138.910Lanthanum
Lantan
Lanthanum is a rare earth element with atomic number 57 and the first element of the lanthanide series in many tables. It is used in optical glass, NiMH batteries, mischmetal, petroleum refining catalysts and lanthanum carbonate medicine.
57
138.91 g/mol
[Xe] 5d¹ 6s²
2 | 8 | 18 | 18 | 9 | 2
1.1
6.162 g/cm³
919.9 °C
3463.8 °C
Carl Gustaf Mosander
Lanthanum was discovered in 1839 by Carl Gustaf Mosander while studying cerium compounds. Its name comes from the Greek lanthanein, meaning to lie hidden, because it had been hidden within cerium minerals.
Lanthanum-138
Natural abundance: About 0.09%. Half-life: About 1.06 x 10¹¹ years. Very long-lived radioactive isotope.Lanthanum-139
Natural abundance: About 99.91%. Dominant stable isotope of lanthanum.La₂O₃
Lanthanum OxideHigh-index optical glass and catalyst support materials.LaNi₅
Lanthanum Nickel AlloyHydrogen-storage alloy used in NiMH battery technology.LaCl₃
Lanthanum(III) ChlorideLewis acid and research precursor.La₂(CO₃)₃
Lanthanum CarbonatePhosphate binder medicine.- Lanthanum oxide in high-refractive-index optical glass for camera and microscope lenses
- Lanthanum-nickel alloys and mischmetal in nickel-metal hydride batteries
- Fluid catalytic cracking catalysts in petroleum refining
- Mischmetal for lighter flints and pyrophoric alloys
- Lanthanum carbonate phosphate binder medicine
Lanthanum has no essential biological role. Lanthanum carbonate is used as a phosphate binder for some dialysis patients to reduce blood phosphate levels.
- Lanthanum gives its name to the lanthanide series even though its exact group-3 classification is sometimes discussed.
- LaNi₅ can reversibly absorb large amounts of hydrogen, which helped battery and hydrogen-storage research.
- Mischmetal is a commercial rare-earth mixture rich in cerium and lanthanum.
- Lanthanum oxide helps produce optical glass with high refractive index and low dispersion.
- Lanthanum has atomic number 57 and electron configuration [Xe] 5d¹ 6s².
- Lanthanum is commonly treated as the first lanthanide or as a group 3 element depending on table style.
- The common oxidation state is +3.
- Remember La₂O₃ for optical glass and LaNi₅ for hydrogen storage and NiMH batteries.
What is the atomic number of lanthanum?
The atomic number of lanthanum is 57.
What is the electron configuration of lanthanum?
Lanthanum has the electron configuration [Xe] 5d¹ 6s².
What is lanthanum used for?
Lanthanum is used in optical glass, NiMH batteries, petroleum refining catalysts, mischmetal and lanthanum carbonate medicine.
Is lanthanum a rare earth element?
Yes. Lanthanum is a rare earth element and is commonly placed at the start of the lanthanide series.
What is lanthanum carbonate used for?
Lanthanum carbonate is used as a phosphate binder for some patients with kidney disease.
Does lanthanum have stable isotopes?
Yes. Natural lanthanum is dominated by stable lanthanum-139, with a tiny amount of very long-lived lanthanum-138.