MCQ
Reason of lanthanoid contraction is
- ✓negligible screening effect of $'f'-$orbitals
- Bincreasing nuclear charge
- Cdecreasing nuclear charge
- Ddecreasing screening effect.
✓
Answer
Correct option: A.
negligible screening effect of $'f'-$orbitals
a
Lanthanoid contraction is the regular decrease in atomic and ionic radii of lanthanides. This is due to the imperfect shielding [or poor screening effect ] of $l-$orbitals due to their diffused shape which unable to counterbalance the effect to the increased nuclear charge. Hence, the net result is a contraction in size of lanthanoids.
Lanthanoid contraction is the regular decrease in atomic and ionic radii of lanthanides. This is due to the imperfect shielding [or poor screening effect ] of $l-$orbitals due to their diffused shape which unable to counterbalance the effect to the increased nuclear charge. Hence, the net result is a contraction in size of lanthanoids.
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