${_{70}Yb^{2+}}$ and ${_{71}Lu^{3+}}$ Lanthanoid ions. .............

Diamagnetic and diamagnetic respectively

The correct answer is Option (2) → Diamagnetic and diamagnetic respectively

Let's analyze the electronic configurations of the given lanthanoid ions:

1. 70Yb²⁺ (Ytterbium(II))

• Atomic number of Yb = 70 → neutral Yb: [Xe] 4f¹⁴ 6s²
• Yb²⁺ → loses 2 electrons → [Xe] 4f¹⁴
• 4f¹⁴ → fully filled → diamagnetic

2. 71Lu³⁺ (Lutetium(III))

• Atomic number of Lu = 71 → neutral Lu: [Xe] 4f¹⁴ 5d¹ 6s²
• Lu³⁺ → loses 3 electrons → [Xe] 4f¹⁴
• 4f¹⁴ → fully filled → diamagnetic

✅ Both ions are diamagnetic