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The d & f Block Elements — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements3 Marks
Question
How would you account for the following?
  1. Transition metals exhibit variable oxidation states.
  2. Zr(z=40) and Hf (Z=72) have almost identical redii.
  3. Transition metals and their compounds act as catalyst.
✓

Answer

  1. Due to incomplete filling of d-orbitals, transition metals show variable oxidation states.
  2. Because of Lanthanoid Contraction.
  3. Because of their ability to show multiple/variable oxidation states.

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