Would you expect the second electron gain enthalpy of `O` as positive, more negative or less negative than the first? Justify your answer.

Explanation

To determine whether the second electron gain enthalpy of oxygen (O) is positive, more negative, or less negative than the first, we can analyze the process step by step.

### Step 1: Understanding Electron Gain Enthalpy
- **Definition**: Electron gain enthalpy is the amount of energy released when an isolated gaseous atom gains an electron. It is typically expressed as a negative value because energy is released during the process.

### Step 2: First Electron Gain Enthalpy of Oxygen
- When an oxygen atom (O) gains its first electron, it becomes an O⁻ ion.
- **Value**: The first electron gain enthalpy of oxygen is approximately -141 kJ/mol. This value is negative because energy is released when the electron is added.
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