Question

Among the following options, select the option in which each complex in Set-I shows geometrical isomerism and the two complexes in Set-II are ionization isomers of each other.
[en = H₂NCH₂CH₂NH₂]

• A. Set-I: [Ni(CO)₄] and [PdCl₂(PPh₃)₂]
  Set-II: [Co(NH₃)₅CI]SO₄ and [Co(NH₃)₅(SO₄)]Cl
• B. Set-I: [Co(en) (NH₃)₂Cl₂] and [PdCl₂(PPh₃)₂]
  Set-II: [Co(NH₃)₆] [Cr(CN)₆] and [Cr(NH₃)₆][Co(CN)₆]
• C. Set-I: [Co(NH₃)₃(NO₂)₃] and [Co(en)₂Cl₂]
  Set-II: [Co(NH₃)₅CI]SO₄ and [Co(NH₃)₅(SO₄)]Cl
• D. Set-I: [Cr(NH₃)₅CI]Cl₂ and [Co(en) (NH₃)₂Cl₂]
  Set-II: [Cr(H₂O)₆]Cl₃ and [Cr(H₂O)₅Cl]Cl₂H₂O

Answer 1

The Correct Option is C

Set-I Analysis: 

• \([Co(NH_3)_3(NO_2)_3]\): This complex is of type \([Mab_3]\), which can exhibit geometrical isomerism with facial (fac) and meridional (mer) isomers.
• \([Co(en)_2Cl_2]\): This complex is of type \([M(AA)_2a_2]\), where (en) is a bidentate ligand, and it shows cis and trans isomerism.

Set-II Analysis:

\([Co(NH_3)_5Cl]SO_4\) and \([Co(NH_3)_5(SO_4)]Cl\): These two complexes are ionization isomers because they differ in the ion released in solution.

• One releases \( Cl^- \).
• The other releases \( SO_4^{2-} \).

Conclusion:

Option (C) satisfies both conditions:

• Geometrical isomerism in Set-I.
• Ionization isomerism in Set-II.