Which of the following will give a pair of enantiomorphs? .

Options

A. `[Pt(NH_(3))_(4)]9PtCI_(6)]`
B. `[Co(NH_(3))_(4)CI_(2)]NO_(2)`
C. `[cr(NH_(3))_(6)][Co(CN)_(6)]`
D. `[co(en)_(2)CI_(2)]CI`(en=`NH_(2)CH_(2)CH_(2)NH_(2))`

Answer

To determine which of the given coordination compounds will give a pair of enantiomers, we need to analyze each option based on their molecular geometry and the presence of chiral centers. Enantiomers are non-superimposable mirror images of each other, typically arising in compounds with chiral centers.

### Step-by-Step Solution:

1. **Understanding Enantiomers**:
- Enantiomers are optical isomers that are non-superimposable mirror images. They usually occur in compounds that have at least one chiral center.

2. **Analyzing the Options**:
- We need to evaluate each coordination compound provided in the options to check for the presence of chiral centers.

3. **Option A**: Coordination compound with similar ligands.
- If the ligands are the same and arranged symmetrically, the compound will not have a chiral center. Therefore, it cannot produce enantiomers.

4. **Option B**: Coordination compound with octahedral geometry.
- In this case, if the ligands are arranged in a symmetrical manner (like in a trans configuration), the mirror images will be superimposable. Thus, it will not yield enantiomers.

5. **Option C**: Another coordination compound with similar ligands.
- Similar to the previous options, if the ligands are the same and arranged symmetrically, it will not exhibit chirality and hence will not produce enantiomers.

6. **Option D**: Coordination compound with bidentate ligands.
- This compound is of the form [Co(en)₂Cl₂], where 'en' represents ethylenediamine, a bidentate ligand.
- In the cis configuration, the two bidentate ligands can create a chiral environment.
- When we draw the cis form, we find that the mirror image of this structure is non-superimposable, indicating the presence of enantiomers.

7. **Conclusion**:
- The only compound that can form a pair of enantiomers is option D, which contains the bidentate ligand ethylenediamine.

### Final Answer:
The answer is option D, which contains the possibility of a pair of enantiomers.