Lanthanum

Atomic number: 57     Symbol: La

Average atomic weight: 138.90547(7) u

IsotopeFractionAtomic weight/u
1380.00090(1)137.907112(4)
1390.99910(1)138.9063533(26)

Atomic weights and isotopic compositions were obtained from NIST Database 144


The Atomic Line List does not contain any data for this element

(Atomic Line List 2.05b16, compiled on Jan 13, 2012)