NEET · Chemistry · STD 12 - 4. d and f- block elements
\(\operatorname{Zr}\,(\mathrm{Z}=40)\) and \(\mathrm{Hf}\,(\mathrm{Z}=72)\) have similar atomic and ionic radii because of :
- A belonging to same group
- B diagonal relationship
- C lanthanoid contraction
- D having similar chemical properties
Answer & Solution
Correct Answer
(C) lanthanoid contraction
Step-by-step Solution
Detailed explanation
From \(IV- A\) to \(II- B\) Due to lanthanoid contration size of \(4 \mathrm{~d}\) \(\&\) \(5 \mathrm{~d}\) series elements of same group are approx same.
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