A sigma bond is formed by the overlapping of

Options

A. Only s-s orbitals
B. Only s-p orbitals
C. s-s, s-p or p-p orbitals along internuclear axis
D. p-p orbitals perpendicular to the internuclear axis

Answer

To answer the question "A sigma bond is formed by the overlapping of," we will go through the steps to understand how sigma bonds are formed.

### Step-by-Step Solution:

1. **Understanding Sigma Bonds**:
- A sigma (σ) bond is the first bond formed between two atoms. It is characterized by the head-on or end-to-end overlap of atomic orbitals.

2. **Types of Overlapping**:
- Sigma bonds are formed through two main types of overlapping:
- **Head-on (Coaxial) Overlap**: This occurs when orbitals overlap directly along the axis connecting the two nuclei of the bonding atoms.
- **Side-on Overlap**: This type of overlap forms pi (π) bonds, which are not relevant for sigma bonds.

3. **Atomic Orbitals Involved**:
- Sigma bonds can be formed by the overlapping of different types of atomic orbitals:
- **S-orbitals with S-orbitals**: When two s-orbitals from different atoms overlap, they form a sigma bond.
- **S-orbitals with P-orbitals**: An s-orbital can overlap with a p-orbital to form a sigma bond.
- **P-orbitals with P-orbitals**: Two p-orbitals can also overlap head-on to form a sigma bond.

4. **Conclusion**:
- Therefore, a sigma bond is formed by the overlapping of:
- S-orbitals with S-orbitals
- S-orbitals with P-orbitals
- P-orbitals with P-orbitals

5. **Final Answer**:
- A sigma bond is formed by the overlapping of S-orbitals and/or P-orbitals.