Which of the following pairs would have a higher negative electron gain enthalpy ?
`{:((i)N or O, (ii) For Cl),((iii)Br or I, (iv) B or Al):}`

Explanation

To determine which of the given pairs has a higher negative electron gain enthalpy, we will analyze each pair based on their electronic configurations and the stability of the resulting anions after gaining an electron.

### Step-by-Step Solution:

1. **Understanding Electron Gain Enthalpy**:
- Electron gain enthalpy is the energy released when an electron is added to a neutral atom. A more negative value indicates that the atom more readily accepts an electron, resulting in a more stable anion.

2. **Comparing Nitrogen (N) and Oxygen (O)**:
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