Which of the following leads to bonding?

Options

A.
B.
C.
D.

Answer

To determine which of the given orbital interactions leads to bonding, we will analyze each option based on the type of overlap between the orbitals involved.

### Step-by-Step Solution:

1. **Identify the Orbitals**:
- We have different combinations of S and P orbitals in the options provided.

2. **Analyze the First Option**:
- The first option involves an S orbital and a P orbital.
- The overlap is unsymmetrical, meaning it does not have a proper head-on or sideways overlap.
- **Conclusion**: This does not lead to bonding.

3. **Analyze the Second Option**:
- The second option also involves an S orbital and a P orbital.
- Here, the P orbital overlaps with the S orbital in a head-on manner, and the phases of the orbitals are the same (both in the positive phase).
- **Conclusion**: This symmetrical overlap leads to bonding.

4. **Analyze the Third Option**:
- The third option consists of two P orbitals.
- The overlap is between two P orbitals with different phases (one positive and one negative).
- **Conclusion**: This results in a negative overlap, which does not lead to bonding.

5. **Analyze the Fourth Option**:
- The fourth option involves an S orbital, a P orbital, and a D orbital.
- Similar to the third option, the overlap is not symmetrical and involves different phases.
- **Conclusion**: This negative overlap does not lead to bonding.

6. **Final Conclusion**:
- After analyzing all options, the only combination that leads to bonding is the second option, where there is a head-on overlap between the S and P orbitals.

### Answer:
The correct answer is **Option 2**.

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