CHILD DEVELOPMENT PEDAGOGY

Detailed explanation-1: -lanthanide, also called lanthanoid, any of the series of 15 consecutive chemical elements in the periodic table from lanthanum to lutetium (atomic numbers 57–71). With scandium and yttrium, they make up the rare-earth metals.

Detailed explanation-2: -lanthanide series, a series of metallic elements, included in the rare-earth metals, in Group 3 of the periodic table. Members of the series are often called lanthanides, although lanthanum (atomic number 57) is not always considered a member of the series.

Detailed explanation-3: -The Lanthanides Lanthanum: symbol Ln, atomic number 57. Cerium: symbol Ce, atomic number 58. Praseodymium: symbol Pr, atomic number 59. Neodymium: symbol Nd, atomic number 60.

Detailed explanation-4: -These rows contain elements in the lanthanoid and actinoid series, usually from 57 to 71 (lanthanum to lutetium) and 89 to 103 (actinium to lawrencium), respectively. There is no scientific reason for this. It is merely done to make the table more compact.