Question
Chemistry Question on d -and f -Block Elements
Which of the following factors may be regarded as the main cause of lanthanide contraction ?
A
Greater shielding of 5d electron by 4f electrons
B
Poorer shielding of 5d electron by 4f electrons
C
Effective shielding of one of 4f electrons by another in the sub-shell
D
Poor shielding of one of 4f electron by another in the sub-shell
Answer
Poor shielding of one of 4f electron by another in the sub-shell
Explanation
Solution
Lanthanide contraction is due to poor shielding of one of 4f electron by another in the sub-shell.