The highest electron affinity is shown by

Options

A. `O^(-)`
B. `F^(-)`
C. `C1_(2)`
D. `F_(2)`

Explanation

To determine which element has the highest electron affinity, we can follow these steps:

### Step 1: Define Electron Affinity
Electron affinity is defined as the amount of energy released when an electron is added to a neutral atom in the gas phase. A higher electron affinity means that an atom is more likely to accept an electron.

**Hint:** Remember that electron affinity is a measure of how much an atom wants to gain an electron.

### Step 2: Identify Elements with High Electron Affinity
Common elements known for high electron affinity include halogens such as fluorine (F), chlorine (Cl), and oxygen (O). Among these, we need to analyze their electron configurations.

**Hint:** Focus on the electron configurations of the elements in question to understand their stability after gaining an electron.

### Step 3: Analyze Electron Configurations
- **Fluorine (F)**: The electron configuration is 1s² 2s² 2p⁵. When it gains one electron, it achieves a stable configuration (1s² 2s² 2p⁶).
- **Chlorine (Cl)**: The electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁵. Gaining an electron also leads to a stable configuration (1s² 2s² 2p⁶ 3s² 3p⁶).
- **Oxygen (O)**: The electron configuration is 1s² 2s² 2p⁴. Gaining one electron leads to a stable configuration (1s² 2s² 2p⁶).

**Hint:** Consider the stability of the electron configurations after gaining an electron; the more stable the configuration, the higher the electron affinity.

### Step 4: Compare Electron Affinities
While all these elements have high electron affinities, fluorine has the highest electron affinity. This is because it is one electron away from achieving a full outer shell, making it very eager to accept an electron.

**Hint:** Remember that the element closest to achieving a full outer shell typically has the highest electron affinity.

### Step 5: Conclusion
Based on the analysis, we conclude that fluorine (F) has the highest electron affinity among the elements discussed.

**Final Answer:** The highest electron affinity is shown by fluorine (F).