Question

More number of oxidation state are exhibited by the actinoids than by lanthanoids. The main reason for this is :

• A. greater metallic character of lanthanoids than that of their corresponding actinoids
• B. more active nature of actinoids
• C. more energy difference between $5f$ and $6d$ orbitals than that between $4f$ and $5d$ orbitals
• D. lesser energy difference between $5f$ and $6d$ orbitals than that between $4f$ and $5d$ orbitals.

Answer 1

Answer: (D)

lesser energy difference between $5f$ and $6d$ orbitals than that between $4f$ and $5d$ orbitals.

Answer 2

More number of oxidation states are exhibited by the actinides than by the lanthanides due to lesser energy difference between $5f$ and $6d$ orbitals than that between $4f$ and $5d$-orbitals.