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NEETChemistryd and f Block Elements

What is the phenomenon associated with the similarity in atomic radii between the third (5d) and second (4d) series of elements?

Options

  1. ALanthanoid contraction.
  2. BNoble gas configuration.
  3. CShielding effect.
  4. DIntervention of 4f orbitals.

Correct answer

D. Intervention of 4f orbitals.

Step-by-step solution

The phenomenon of similar atomic radii between the third (5d) and second (4d) series is associated with the intervention of the 4f orbitals.

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