MCQ
The Lanthanoid contraction refers to decrease in the:
- AValence electrons of the Lanthanide series.
- ✓Ionic radius of the series.
- CThe density of the series.
- DNuclear mass of the series.
✓
Answer
Correct option: B.
Ionic radius of the series.
The Lanthanoid contraction refers to decrease in the ionic radius of the series. It is a reduction in atomic/ionic size with increase in atomic number. This is due to poor shielding of $4f$ electrons.
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