`CO_(2)` is iso-structural with :

Options

A. `HgCl_(2)`
B. `C_(2)H_(2)`
C. `SnCl_(2)`
D. `NO_(2).`

Explanation

To determine which compounds are iso-structural with CO₂, we need to analyze the structure and hybridization of CO₂ and compare it with other compounds.

### Step-by-Step Solution:

1. **Identify the Structure of CO₂**:
- CO₂ (carbon dioxide) has a linear structure. This is because the carbon atom forms two double bonds with two oxygen atoms (O=C=O).
- The hybridization of the carbon atom in CO₂ is sp, as it forms two sigma bonds and has no lone pairs.

2. **Determine the Iso-Structural Condition**:
- For two compounds to be iso-structural, they must have the same shape and hybridization. Therefore, we are looking for compounds that also have a linear shape and sp hybridization.

3. **Analyze Potential Candidates**:
- **HgCl₂ (Mercury(II) chloride)**:
- The structure is linear, as mercury forms two bonds with chlorine (Cl-Hg-Cl).
- The hybridization of mercury in this compound is also sp.
- Thus, HgCl₂ is iso-structural with CO₂.

- **C₂H₂ (Ethyne or Acetylene)**:
- The structure is linear, as it has a triple bond between the two carbon atoms (H-C≡C-H).
- The hybridization of each carbon atom is also sp.
- Therefore, C₂H₂ is iso-structural with CO₂.

- **SnCl₂ (Tin(II) chloride)**:
- The structure is angular due to the presence of a lone pair on tin, leading to a bent shape.
- The hybridization of tin in this compound is sp².
- Thus, SnCl₂ is not iso-structural with CO₂.

- **NO₂ (Nitrogen dioxide)**:
- The structure is also angular due to the presence of an unpaired electron and one lone pair on nitrogen.
- The hybridization of nitrogen in NO₂ is sp².
- Therefore, NO₂ is not iso-structural with CO₂.

4. **Conclusion**:
- The compounds that are iso-structural with CO₂ are **HgCl₂** and **C₂H₂**.

### Final Answer:
CO₂ is iso-structural with **HgCl₂** and **C₂H₂**.

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