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

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements5 Marks
Question
  1. Give three points of difference between lanthanoids and actinoids.
  2. Give reason and select one atom/ion which will exhibit asked property:
  1. Sc3+ or Cr3+ (Exhibit diamagnetic behaviour).
  2. Cr or Cu (High melting and boiling point).
✓

Answer

  1.  
S. No.
Lanthanoids
Actinoids
1.
Most of them are not radioactive.
All are radioactive.
2.
Don’t show a wide range of oxidation state.
Show a wide range of oxidation states.
3.
Most of their ions are colourless.
Most of their ions are coloured.
  1.  
  1. Sc+3, because of absence of unpaired electron.
  2. Cr, because of presence of strong intermetallic bonding than Cu.

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