Alkaline earth metals always form divalent cations even through their second ionization enthalpies are almost double than their first ionization enthalpies . Explain .

Explanation

To explain why alkaline earth metals always form divalent cations (M²⁺) despite their second ionization enthalpies being almost double their first ionization enthalpies, we can break down the reasoning into several steps:

### Step 1: Understanding Ionization Energies
- **First Ionization Energy (IE1)**: This is the energy required to remove the first electron from a neutral atom of an alkaline earth metal (M → M⁺ + e⁻).
- **Second Ionization Energy (IE2)**: This is the energy required to remove a second electron from the singly charged cation (M⁺ → M²⁺ + e⁻).

### Step 2: Comparing Ionization Energies
- For alkaline earth metals, the second ionization energy (IE2) is significantly higher than the first ionization energy (IE1). This means that it requires much more energy to remove the second electron compared to the first.
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