MCQ
The Lanthanoids contraction relates to:
- AAtomic radii.
- ✓Atomic as well as $\mathrm{M}^{3+}$ radii.
- CValence electrons.
- DOxidation states.
✓
Answer
Correct option: B.
Atomic as well as $\mathrm{M}^{3+}$ radii.
The Lanthanoids contraction relates to atomic as well as $\mathrm{M}^{3+}$ radii.
The atomic and ionic radii $(\mathrm{M}^{3+}$ ions$)$ of Lanthanide elements decrease with increase in atomic number. This effect is called Lanthanoid contraction. This is due to poor shielding of $4f$ electrons.
The atomic and ionic radii $(\mathrm{M}^{3+}$ ions$)$ of Lanthanide elements decrease with increase in atomic number. This effect is called Lanthanoid contraction. This is due to poor shielding of $4f$ electrons.
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