D And F Block Elements

14 elements in the sixth period (atomic number \(=58\) to 71 ) that are filling \(4 f\)-sublevel.

common oxidation state is +3 .

Availability of \(4 f\)-electrons results in the formation of compounds in +4 state for all numbers of the series.

There is a gradual decrease in the of the elements with increasing atomic numbers in the series.