Which of the following molecules has both `p_(pi)-p_(pi) and p_(pi)-d_(pi)` bonds

Options

A. `XeO_(2)F_(2)`
B. `SO_(2)Cl_(2)`
C. `SO_(3)`
D. `XeO_(3)`

Answer

To determine which molecule has both \( p_{\pi}-p_{\pi} \) and \( p_{\pi}-d_{\pi} \) bonds, we will analyze the bonding in the given options, focusing on the molecule \( SO_3 \) (sulfur trioxide).

### Step-by-Step Solution:

1. **Identify the Central Atom**:
- In \( SO_3 \), the central atom is sulfur (S).

2. **Determine the Valence Electrons**:
- Sulfur has an atomic number of 16. Its electronic configuration is \( [Ne]3s^2 3p^4 \). Therefore, sulfur has 6 valence electrons (2 from \( 3s \) and 4 from \( 3p \)).

3. **Calculate the Hybridization**:
- The formula for hybridization is given by:
\[ \text{Hybridization} = \frac{1}{2} \left( \text{Number of valence electrons of central atom} + \text{Number of monovalent atoms surrounding it} \right) \]
- In \( SO_3 \), there are 3 oxygen atoms surrounding sulfur.
- Therefore, the hybridization of sulfur in \( SO_3 \) is:
\[ \text{Hybridization} = \frac{1}{2} \left( 6 + 0 \right) = 3 \quad \text{(which corresponds to } sp^2 \text{ hybridization)} \]

4. **Determine the Type of Bonds Formed**:
- In \( SO_3 \), sulfur uses its \( sp^2 \) hybridized orbitals to form sigma bonds with the three oxygen atoms.
- The remaining \( p \) orbital on sulfur can form \( p_{\pi}-p_{\pi} \) bonds with the \( p \) orbitals of oxygen.

5. **Check for \( p_{\pi}-d_{\pi} \) Bonds**:
- Sulfur also has vacant \( d \) orbitals (3d), which can participate in bonding.
- In \( SO_3 \), the \( p \) orbital of sulfur can overlap with the \( d \) orbitals of another atom (if present) to form \( p_{\pi}-d_{\pi} \) bonds.

6. **Conclusion**:
- Thus, in \( SO_3 \), there are both \( p_{\pi}-p_{\pi} \) bonds (between sulfur and oxygen) and \( p_{\pi}-d_{\pi} \) bonds (due to the involvement of sulfur's vacant \( d \) orbitals).
- Therefore, the molecule that has both types of bonds is \( SO_3 \).

### Final Answer:
The molecule that has both \( p_{\pi}-p_{\pi} \) and \( p_{\pi}-d_{\pi} \) bonds is **\( SO_3 \)**.