Match the complex species given in Column I with the possible isomerism given in Column II and assign the correct code :
`{:(,"Column I (Complex species)",,"Column II (Isomerism)"),("A".,[Co(NH_(3))_(4)Cl_(2)]^(+),1.,"optical"),("B".,cis-[Co(en)_(2)Cl_(2)]^(+),2.,"ionisation"),("C".,[Co(NH_(3))_(5)(NO_(2))]Cl_(2),3.,"coordination"),("D".,[Co(NH_(3))_(6)][Cr(CN)_(6)],4.,"geometrical"),(,,5.,"linkage"):}`

Options

A. `{:("A (1)","B (2)","C (4)","D (5)"):}`
B. `{:("A (4)","B (3)","C (2)","D (1)"):}`
C. `{:("A (4)","B (1)","C (5)","D (3)"):}`
D. `{:("A (4)","B (1)","C (2)","D (3)"):}`

Answer

To solve the problem of matching the complex species in Column I with the possible isomerism in Column II, we will analyze each complex species and determine the type of isomerism it can exhibit.

### Step-by-Step Solution:

1. **Identify Complex A: [Co(NH₃)₄Cl₂]⁺**
- This complex has 4 ammonia (NH₃) ligands and 2 chloride (Cl) ligands.
- Since it has different types of ligands, it can exhibit **geometrical isomerism** (cis-trans).
- **Conclusion**: A = 4 (Geometrical isomerism)

2. **Identify Complex B: cis-[Co(en)₂Cl₂]⁺**
- This complex has 2 ethylenediamine (en) ligands and 2 chloride (Cl) ligands.
- The cis form can be optically active due to the lack of a plane of symmetry, while the trans form would be optically inactive.
- **Conclusion**: B = 1 (Optical isomerism)

3. **Identify Complex C: [Co(NH₃)₅(NO₂)]Cl₂**
- This complex has 5 ammonia (NH₃) ligands and 1 nitrito (NO₂) ligand, along with 2 chloride ions.
- It can exhibit **ionization isomerism** because when it dissociates, the nitrito ligand can be part of the coordination sphere or outside of it.
- **Conclusion**: C = 2 (Ionization isomerism)

4. **Identify Complex D: [Co(NH₃)₆][Cr(CN)₆]**
- This complex consists of two different coordination spheres: one with cobalt and one with chromium.
- It can exhibit **coordination isomerism** because the ligands can be exchanged between the two metal centers.
- **Conclusion**: D = 5 (Coordination isomerism)

### Final Matching:
- A = 4 (Geometrical isomerism)
- B = 1 (Optical isomerism)
- C = 2 (Ionization isomerism)
- D = 5 (Coordination isomerism)

### Summary of Codes:
- A - 4
- B - 1
- C - 2
- D - 5