Chemistry · Lanthanoids: Electronic configuration, oxidation states and Lanthanoid contraction

Which of the following factors may be regarded as the main cause of lanthanide c

Which of the following factors may be regarded as the main cause of lanthanide contraction?

  • A. Greater shielding of 5 d-electron by 4 f-electrons
  • B. Poor shielding of 5 d-electron by 4 f-electrons
  • C. Effective shielding of one 4 f-electrons by another in the subshel
  • D. Poor shielding of one of 4-electrons by another in the subshell

Step-by-step solution

Lanthanide contraction is primarily due to the poor shielding effect of 4f electrons. As the 4f subshell is filled across the lanthanide series, each additional 4f electron inadequately shields the nuclear charge, leading to an increase in effective nuclear charge. This causes a contraction in atomic and ionic radii.
Practise more in this unitView MCQsSign up for full question bank