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QNEET-2021-Ch-573: NEET 2021 Chemistry - Class 12 NEET-2021-Ch-573 Solution: Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii …
Zr (Z = 40) and Hf (Z = 72) have similar atomic and ionic radii because of: Having similar chemical properties Belonging to same group Diagonal relationship Lanthanoid contraction
Multiple Choice Options
- A Having similar chemical properties
- B Belonging to same group
- C Diagonal relationship
- D Lanthanoid contraction
Step-by-Step Verified Solution
_ Hf is a post lanthanoid element. Due to presence of4f-orbitals which have poor shielding effect, the effective nuclear charge on valence shell electrons is more which result in the decrease of the size of Hf. This effect is known as lanthanoid contraction.
_ The almost identical radii of Zr (160 pm) and Hf (159 pm) is a consequence of the lanthanoid contraction.