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NEETChemistryd and f Block Elements

What is the cause of the lanthanoid contraction?

Options

  1. AThe perfect shielding of one electron by another
  2. BThe imperfect shielding of one electron by another
  3. CThe regular decrease in atomic radii
  4. DThe irregular decrease in atomic radii

Correct answer

B. The imperfect shielding of one electron by another

Step-by-step solution

The lanthanoid contraction is attributed to "the imperfect shielding of one electron by another in the same sub-shell."

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