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99 Percentile Qs Bank for JEE MainChemistryd and f Block Elements

Lanthanoid contraction is due to:

Options

  1. ANegligible screening effect of 4 f orbitals.
  2. BNegligible screening effect of 5 f orbital.
  3. CDecreasing nuclear charge.
  4. DIncreasing screening effect.

Correct answer

A. Negligible screening effect of 4 f orbitals.

Step-by-step solution

Lanthanide contraction : There is a decrement in the size of the atoms and ions of the f - block elements with increasing atomic number from La having atomic number 57 through Lu having atomic number 71 . Weak screening effect of the 4 f - electrons called Lanthanide contraction

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