The species in which the central atom uses `sp^2` hybrid orbitals in its bonding is

Options

A. `SO_2`
B. `PH_3`
C. `NH_3`
D. `SbH_3`

Answer

To determine which species has a central atom that uses `sp^2` hybrid orbitals in its bonding, we can analyze the given options based on their molecular geometry and bonding characteristics.

### Step-by-Step Solution:

1. **Identify the Hybridization Concept**:
Hybridization is the mixing of atomic orbitals to form new hybrid orbitals that can form sigma bonds with other atoms. The type of hybridization can be determined by the number of sigma bonds and lone pairs around the central atom.

2. **Analyze the Given Options**:
We need to check each option to see if the central atom exhibits `sp^2` hybridization. `sp^2` hybridization occurs when there are three sigma bonds and no lone pairs on the central atom.

3. **Consider SO2 (Sulfur Dioxide)**:
- The central atom is sulfur (S).
- The structure of SO2 shows that sulfur is bonded to two oxygen atoms with a double bond to one and a single bond to the other.
- This results in a total of **three sigma bonds** (one from each double bond and one from the single bond).
- There are **no lone pairs** on the sulfur atom.
- Therefore, the hybridization of sulfur in SO2 is **`sp^2`**.

4. **Check Other Options**:
- **PH3 (Phosphine)**: Phosphorus has three sigma bonds and one lone pair, leading to `sp^3` hybridization.
- **NH3 (Ammonia)**: Nitrogen has three sigma bonds and one lone pair, leading to `sp^3` hybridization.
- **SiH4 (Silane)**: Silicon has four sigma bonds and no lone pairs, leading to `sp^3` hybridization.

5. **Conclusion**:
The only species where the central atom uses `sp^2` hybrid orbitals is **SO2**.

### Final Answer:
The species in which the central atom uses `sp^2` hybrid orbitals in its bonding is **SO2**.

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