Why `MgO` exist as `Mg^(2+)O^(2-)` not as `Mg^(o+)O^(ɵ)` whereas the formation of `Mg^(2+)` from `Mg` requires more energy than formation of `Mg^(o+)` and formation of `O^(ɵ)` from `O` is exothermic whereas the formation of `O^(2-)` is endothermic .

Explanation

To understand why MgO exists as Mg²⁺O²⁻ rather than Mg⁺O⁻, we need to analyze the energy changes involved in the formation of these ions and the stability of the resulting ionic compound. Here's a step-by-step breakdown:

### Step 1: Ion Formation of Magnesium
- **Formation of Mg²⁺ from Mg**:
- Magnesium (Mg) has the electronic configuration of [Ne]3s². To form Mg²⁺, two electrons must be removed, resulting in the configuration [Ne], which is stable.
- The first ionization energy (IE₁) is the energy required to remove the first electron, and the second ionization energy (IE₂) is the energy required to remove the second electron.
- Although IE₂ is higher than IE₁, the formation of Mg²⁺ is favorable because it achieves a noble gas configuration.

...