`p pi - p pi` multiple bond is seen in

Options

A. Mostly carbon
B. All carbon family member
C. Sn but not in carbon
D. Boron family and not in carbon family

Answer

To solve the question regarding the presence of p pi - p pi multiple bonds, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding p pi - p pi Bonds**:
- p pi - p pi bonds are formed when two p orbitals from different atoms overlap sideways. This type of bonding is typically seen in elements that can form multiple bonds, such as double or triple bonds.

2. **Identifying Relevant Elements**:
- The question provides four options, and we need to identify which of these elements can form p pi - p pi multiple bonds. The most common elements known for forming such bonds are from the carbon family (Group 14 of the periodic table).

3. **Catenation Tendency**:
- Catenation is the ability of an element to form chains or rings of atoms through covalent bonds. Carbon has a strong catenation tendency, allowing it to bond with itself and form various allotropes (like diamond, graphite, etc.).

4. **Analyzing the Options**:
- **Option A (Carbon)**: Carbon can form p pi - p pi multiple bonds due to its ability to catenate and form double (C=C) and triple (C≡C) bonds.
- **Option B (Silicon)**: Silicon can form some multiple bonds but has a weaker catenation tendency compared to carbon.
- **Option C (Tin)**: Tin does not typically form p pi - p pi multiple bonds.
- **Option D (Boron)**: While boron can form some types of bonds, it does not exhibit the same p pi - p pi bonding as carbon.

5. **Conclusion**:
- Based on the analysis, the correct answer is **Option A (Carbon)**, as it is the element that predominantly exhibits p pi - p pi multiple bonding due to its strong catenation tendency.

### Final Answer:
The p pi - p pi multiple bond is seen in **Carbon**.

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