Which halogen has the gretest electron affinity?

Explanation

To determine which halogen has the greatest electron affinity, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Electron Affinity**:
- Electron affinity is the energy change that occurs when an electron is added to a neutral atom in the gas phase. It is a measure of how much an atom wants to gain an electron.
- The process is generally exothermic, meaning energy is released when an electron is added.

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