Lanthanum
= Lanthanum
{title2=$\mathrm{La}$}
{wiki}
<Lanthanum> is the <chemical element> with <atomic number> 57 and symbol $\mathrm{La}$. It is a <metal>. The $+3$ oxidation state dominates its chemistry. Lanthanum compounds occur in optical glasses and catalytic materials; the properties of those compounds should be distinguished from the reactive silvery elemental metal.<Periodic Table by Royal Society of Chemistry>[Lanthanum, element data and uses]{ref}