Which of the following species has the highest electron affinity ?

Options

A. `F^(-)`
B. `O `
C. `O^(-)`
D. `Na^(+)`

Explanation

To determine which of the following species has the highest electron affinity, we need to analyze the electron affinity of each species provided.

### Step-by-Step Solution:

1. **Understanding Electron Affinity**:
- Electron affinity is the amount of energy released when an electron is added to a neutral atom in the gaseous state. A higher electron affinity means that the atom more readily accepts an electron.

2. **Analyzing the Given Species**:
- Let's consider the species mentioned: \( F^- \), \( O^- \), and \( Na^+ \).

3. **Evaluating \( F^- \) and \( O^- \)**:
- Both \( F^- \) and \( O^- \) already have a negative charge, which means they have extra electrons. When we try to add another electron to these negatively charged ions, there will be electron-electron repulsion. This repulsion means that energy will not be released; instead, energy would need to be supplied to add another electron. Therefore, neither \( F^- \) nor \( O^- \) will have a high electron affinity.

4. **Evaluating \( Na^+ \)**:
- The configuration of \( Na^+ \) is \( 1s^2 2s^2 2p^6 \), which is a stable noble gas configuration (like Neon). Since it is already stable, it is unlikely to accept an electron readily. Thus, \( Na^+ \) will also not have a high electron affinity.

5. **Evaluating Oxygen (O)**:
- Oxygen, in its neutral state, has the configuration \( 1s^2 2s^2 2p^4 \). It is two electrons short of achieving a stable noble gas configuration. Therefore, it has a strong tendency to accept an electron, and when it does, energy is released. This indicates that oxygen has a high electron affinity.

6. **Conclusion**:
- Among the species analyzed, oxygen has the highest electron affinity because it readily accepts an electron and releases energy in the process.

### Final Answer:
- The species with the highest electron affinity is **Oxygen (O)**.