MCQ
Reason of lanthanoid contraction is
- ✓Negligible screening effect of $'4f'$ orbitals
- BNegligible screening effect of $'5f'$ orbital
- CDecreasing nuclear charge
- DIncreasing screening effect
✓
Answer
Correct option: A.
Negligible screening effect of $'4f'$ orbitals
a
Due to poor shielding of $4f-$ orbitals, nucleus will exert a strong attraction, Causes lanthanoid contraction.
Due to poor shielding of $4f-$ orbitals, nucleus will exert a strong attraction, Causes lanthanoid contraction.
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