The strength of bonds formed by overlapping of `2s-2s`, `2p-2p` and `2p-2s` follows the order

Options

A. `2s-2s gt 2p-2p gt 2s-2p`
B. `2s-2sgt 2p-2s gt 2p-2p`
C. `2p-2pgt2s-2pgt 2s-2s`
D. `2p-2p gt 2s-2s gt 2p-2s`

Answer

To determine the strength of bonds formed by the overlapping of `2s-2s`, `2p-2p`, and `2p-2s` orbitals, we can analyze the nature of these overlaps step by step.

### Step-by-Step Solution:

1. **Identify the Types of Overlaps:**
- We have three types of overlaps to consider:
- `2s-2s`
- `2p-2p`
- `2p-2s` (which is the same as `2s-2p`)

2. **Understanding Orbital Shapes:**
- The `s` orbital is spherical in shape, while the `p` orbital has a dumbbell shape. This difference in shape affects how effectively the orbitals can overlap.

3. **Evaluate Overlap Strength:**
- **2p-2p Overlap:**
- This overlap is considered the strongest because both orbitals are of the same type (p orbitals) and can align effectively to maximize overlap.
- **2p-2s Overlap:**
- The overlap between a p orbital and an s orbital is less effective than p-p overlap but more effective than s-s overlap. The p orbital can interact with the spherical s orbital, leading to a moderate bond strength.
- **2s-2s Overlap:**
- The overlap between two s orbitals is the weakest among the three types. While they can overlap, the spherical nature of the s orbitals does not allow for as effective a bond as the p orbitals.

4. **Order of Bond Strength:**
- Based on the analysis above, we can establish the order of bond strength from strongest to weakest:
- **2p-2p > 2p-2s > 2s-2s**

5. **Conclusion:**
- Therefore, the strength of bonds formed by overlapping of `2s-2s`, `2p-2p`, and `2p-2s` follows the order:
- **2p-2p > 2p-2s > 2s-2s**

### Final Answer:
The order of bond strength is: **2p-2p > 2p-2s > 2s-2s**.