A mixture of two or more metals.
The number of protons in the nucleus of an atom. Since this number is different for each element, elements are listed on the periodic table of elements in order of atomic number.
An atom or atoms that has lost or gained one or more electrons, and thus has a net electrical charge.
A progressive decrease in the radius of lanthanide atoms as they increase in atomicnumber.
A group of 14 elements, with atomic numbers 58 through71, that follow lanthanum on the periodic table of elements.
The lanthanide series, along with lanthanum.
A compound formed by the chemical bonding of a metal with oxygen.
A chart showing the elements arranged in order of atomic number, grouping them according to common characteristics.
An old name for the lanthanides, reflecting the difficulty of separating them from compounds containing other lanthanides or other substances.
Groups 3 through 12 on the IUPAC or European version of the periodic table of elements. The lanthanides and actinides, which appear at the bottom of the periodic table, are "branches" of this family.