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Lanthanum (La): Fun Facts and Information About the Element


What is the symbol? La
What is the atomic number? 57
What is the atomic weight? 138.9055
What is the melting point in Celsius? 920
What is the boiling point in Celsius? 3469
What is the density (g/cm3)? 6.15
What year was it discovered? 1839
Who discovered the element? Carl Gustaf Mosander
What group is the element in? 3
What is the electron configuration? [Xe] 5d1 6s2
What is the ionization energy? 5.5769
What element category is it in? Lanthanoids

Where is Lanthanum Found?

Lanthanum is found in rare-earth minerals such as cerite, monazite, allanite, and bastnasite. Monazite and bastnasite are principal ores in which lanthanum occurs in percentages up to 25 percent and 38 percent respectively. The metal can be produced by reducing the anhydrous fluoride with calcium .

What is Lanthanum Used For?

Rare-earth compounds containing lanthanum are extensively used in carbon lighting applications, especially by the motion picture industry for studio lighting and projection. La2O3 improves the alkali resistance of glass, and is used in making special optical glasses.

There is current interest in hydrogen sponge alloys containing lanthanum. These alloys take up to 400 times their own volume of hydrogen gas, therefore these alloys have possibilities in an energy conservation system.