Question

Write down two similarities between lanthanoids and actinoids.

Hint:

Lanthanoids involve filling of 4f orbitals, while actinoids involve filling of 5f orbitals, leading to many similarities in size and chemistry.

Answer 1

Step 1: In both lanthanoids and actinoids, electrons are progressively filled in the inner \(f\)-orbitals (4f in lanthanoids and 5f in actinoids).
Step 2: Both series predominantly exhibit the +3 oxidation state, which is the most stable oxidation state for elements of both groups.