Year: 2017
Topic: The d-and f-Block Elements
Time :
1.
The reason for greater range of oxidation states in actinoids is attributed to
(1). 4f and 5d levels being close in energies.
(2). the radioactive nature of actinoids.
(3). actinoid contraction.
(4). 5f, 6d and 7s levels having comparable energies.