Question

Lanthanoid contraction is caused due to :

• A. the appreciable shielding on outer electrons by 4f electrons from, the nuclear charge
• B. the appreciable shielding on outer electrons by 5d electrons from the nuclear charge
• C. the same effective nuclear charge from Ce to Lu
• D. the imperfect shielding on outer electrons by 4f electrons from the nuclear charge

Answer 1

Answer: (D)

Lanthanoid contraction is due to ineffective shielding produced by larger f-subshell.