Which of the following oxidation state is common for all lanthanoids?

1.  +2

2.  +3

3.  +4

4.  +5

NEETprep Answer: Lanthanoids show a common oxidation state of +3. Some of which also show +2 and +4 stable oxidation states along with +8 oxidation state. These are shown by those elements which by losing 2 or 4 electrons acquire a stable configuration of f0 , f7 or f14 , e.g., Eu2+ is Xe4f7, Yb2+ is Xe4f0 and Tb4f0 and Tb4l is Xe4f7.