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

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements1 Mark
MCQ
Identify a 'Chemical twin' among the followings.
  • A
    Zr - Ta
  • B
    Nb - Tc
  • C
    Hf - Re
  • D
    Nb - Ta
✓

Answer

  1. Nb - Ta

Explanation:

Chemical twins are those in which the properties of some elements are same. Atomic size of Zr and Hf , Nb and Ta are similar. This is due to lanthanide contraction.

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