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NEET2021Chemistryd and f Block ElementsActual

Zr ( Z = 40 ) and Hf ( Z = 72 ) have similar atomic and ionic radii because of:

Options

  1. Abelonging to same group
  2. Bdiagonal relationship
  3. Clanthanoid contraction
  4. Dhaving similar chemical properties

Correct answer

C. lanthanoid contraction

Step-by-step solution

Zr 40 and Hf 72 have similar atomic and ionic radii because of Lanthanoid Contraction. The 4 f orbital offers very poor screening. So, the radius (atomic as well as Ionic) of Zr and Hf are almost the same.

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