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Questions
Why do zirconium and Hafnium exhibit similar properties?
Explain why Zr and Hf exhibit similar properties.
(At. no. of Zr = 40, Hf = 72)
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Solution
- The elements of the second and third transition series resemble each other more closely than the elements of the first and second transition series due to lanthanoid contraction.
- e.g., Zr-4d series -Atomic radius 145 pm Hf-5d series – Atomic radius 144 pm
- The radii are very similar, even though the number of electrons increases.
- Zr and Hf have very similar chemical behaviour, having closely similar radii and electronic configurations.
- Radius-dependent properties such as lattice energy and solvation energy are similar.
- Thus, lanthanide contraction leads to the formation of pairs of elements and those known as chemical twins, e.g., Zr-Hf
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In the light of the above statements, choose the correct answer from the options given below.
