In context with the lanthanoids and actinoids which of the following statements is incorrect?
1) Compared with lanthanoids the lower oxidation states are less important and the higher oxidation states are more important.
2) The 5f electrons of actinoids are more easily removed than the 4f electrons of lanthanoids.
3) Actinoids exhibit greater variation in oxidation states as compared with lanthanoids.
4) The +3 oxidation state in lanthanoid is much less common than that in actinoids.
