Of the two elements given in each of the following cases, choose the element having a more negative electron gain enthalpy. Explain.
F and Cl

Explanation

To determine which of the two elements, fluorine (F) or chlorine (Cl), has a more negative electron gain enthalpy, we can follow these steps:

### Step 1: Understand Electron Gain Enthalpy
Electron gain enthalpy is the amount of energy released or absorbed when an electron is added to a neutral gaseous atom. A more negative value indicates that more energy is released when the electron is added, which means the atom becomes more stable after gaining the electron.

### Step 2: Compare the Electron Configurations
- **Fluorine (F)**: The electron configuration is 1s² 2s² 2p⁵. This means it has 7 electrons in total and needs one more electron to achieve a stable noble gas configuration (1s² 2s² 2p⁶).
- **Chlorine (Cl)**: The electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁵. Chlorine has 17 electrons and also needs one more electron to achieve stability (1s² 2s² 2p⁶ 3s² 3p⁶).
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