Pi `(pi)` bond is formed by the overlap of

Options

A. Option 1. s-s orbitals
B. Option 2. s- p orbitals
C. Option 3. p-p orbitals in end to end manner
D. Option 4. p-p orbitals in sidewise manner

Answer

To determine how a pi (π) bond is formed, we need to analyze the overlap of different types of orbitals. Let's go through the options step by step.

### Step 1: Analyze ss Overlap
- **Description**: The first option is ss overlap, which involves two s orbitals.
- **Explanation**: S orbitals are spherical in shape. When two s orbitals overlap, they do so in a head-on manner. This type of overlap results in the formation of a sigma (σ) bond, not a pi (π) bond.
- **Conclusion**: Therefore, ss overlap does not form a pi bond.

### Step 2: Analyze sp Overlap
- **Description**: The second option is sp overlap, which involves one s orbital and one p orbital.
- **Explanation**: The overlap between an s orbital and a p orbital occurs in a head-on manner. The s orbital can overlap with one lobe of the p orbital, forming a sigma bond. Since this overlap is not sidewise, it cannot form a pi bond.
- **Conclusion**: Therefore, sp overlap does not form a pi bond.

### Step 3: Analyze pp Overlap (End-to-End)
- **Description**: The third option is pp overlap, which involves two p orbitals overlapping end-to-end.
- **Explanation**: When two p orbitals overlap in an end-to-end manner, they also form a sigma bond. This is because the overlap occurs along the axis of the orbitals, which is characteristic of sigma bonding.
- **Conclusion**: Therefore, pp overlap in an end-to-end manner does not form a pi bond.

### Step 4: Analyze pp Overlap (Sidewise)
- **Description**: The fourth option is pp overlap, which involves two p orbitals overlapping sidewise.
- **Explanation**: When two p orbitals overlap sidewise, they create regions of electron density above and below the axis of the bond. This type of overlap is characteristic of pi bonding, as it allows for the formation of a bond that is not restricted to the axis between the two nuclei.
- **Conclusion**: Therefore, pp overlap in a sidewise manner forms a pi bond.

### Final Answer
The correct answer is that a pi (π) bond is formed by the sidewise overlap of p orbitals.

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