Bond formation is:

Options

A. always exothermic
B. always endothermic
C. neither exothermic nor endothermic
D. sometimes exothermic and sometimes endothermic

Answer

### Step-by-Step Text Solution:

1. **Understanding Bond Formation**:
- Bond formation refers to the process where two atoms come together to form a stable molecule. This process is driven by the atoms' desire to achieve a more stable electronic configuration.

2. **Stability as a Driving Force**:
- Atoms tend to bond with each other to attain stability. This stability is often achieved by filling their outer electron shells, which leads to a lower energy state for the system.

3. **Energy Changes During Bond Formation**:
- When a bond forms, energy is either released or absorbed. In most cases, bond formation is an exothermic process, meaning that energy is released into the surroundings.

4. **Exothermic vs. Endothermic**:
- **Exothermic Reaction**: This is a process where energy is released. In the context of bond formation, when two atoms bond, the energy released contributes to the stability of the molecule.
- **Endothermic Process**: This is a process where energy is absorbed. This usually occurs when bonds are broken rather than formed.

5. **Conclusion**:
- Therefore, bond formation is primarily an exothermic process that leads to the release of energy, contributing to the stability of the resulting molecule.

### Final Answer:
Bond formation is an exothermic process that occurs for the purpose of achieving stability in the system.

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