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NEETChemistryd and f Block Elements

What causes the irregular decrease in atomic radii in the lanthanoid series?

Options

  1. APerfect shielding
  2. BImperfect shielding
  3. CNuclear charge
  4. DRegular arrangement of electrons

Correct answer

B. Imperfect shielding

Step-by-step solution

The irregular decrease in atomic radii in the lanthanoid series is due to "the imperfect shielding of one electron by another in the same subshell."

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