Lanthanide for which +II and +III oxidation states are common is

Lanthanide for which +2 and +3 oxidation states are common in La Nd Ce Eu

The lanthanide which do not exhibit +2 oxidation state is

Three lanthanides which show +2 oxidation state also :

Name the members. of the lanthanide series which exhibit +4 oxidation states and those which exhibit +2 oxidation states. Try to correlate this type of behaviour with the electiconic configurations of these elements.

The common oxidation states of Ti are