Lanthanum

Statistics:

• Name: Lanthanum
• Symbol: La
• Classification: Lanthanide
• Atomic Number: 57
• Atomic Mass: 138.90547 g/mol
• Density: 6.16 g/cm³
• Melting: 920°C
• Boiling: 3454°C
• Protons & Electrons:57
• Neutrons:82
• Discovered: 1839
• Discovered By: Mosander
• Sponsored By: Your Ad Here

Electrons Per Energy Level:

• Level 1: 2
• Level 2: 8
• Level 3: 18
• Level 4: 18
• Level 5: 9
• Level 6: 2

Isotopes:

Isotope: Half-life

• ¹³⁴La: 6.45 minutes
• ¹³⁷La: 6e4 years
• ¹³⁸La: 1.05e+11 years
• ¹³⁹La: stable
• ¹⁴⁰La: 1.6781 days
• ¹⁴¹La: 3.92 hours
• ¹⁴²La: 91.1 minutes

Brief Summary

Lanthanum is a Lanthanide with the symbol 'La' and contains 57 Protons & Electrons with 82 neutrons in the nucleus of the atom. Lanthanum has an atomic mass of 138.90547 g/mol and, at a temperature of 20°C, has a density of 6.16 g/cm³. It will melt at a temperature of 920°C and boil at 3454°C.

Lanthanum was discovered by Mosander in 1839 and is named 'Lanthanum' Greek word "lanthaneis" meaning "to lie hidden".

Some common usages for Lanthanum: expensive camera lenses.

Definitions and Notes

Density listed is at a temperature of 20°C.

Isotopes are forms of an element who have the same atomic number but different mass because they contain different number of neutrons.

Half-life is the time required for a quantity of a subject to fall to half of its current quantity.

MLA Citing Format

Lanthanum :: La :: 57 - Chemical Element. 11 Mar. 2010 <http://www.chemicalelement.com/element/lanthanum.html>.