Arrange the following isoelectronic species `(O^(2-) , F^(-) , Na^+, Mg^(2+))` in order of:
increasing ionization energy

Explanation

To arrange the isoelectronic species \( O^{2-}, F^{-}, Na^{+}, Mg^{2+} \) in order of increasing ionization energy, we will follow these steps:

### Step 1: Identify the Number of Electrons
All the given species are isoelectronic, meaning they have the same number of electrons. Each species has 10 electrons:
- \( O^{2-} \): Gains 2 electrons (8 protons + 2 electrons = 10 electrons)
- \( F^{-} \): Gains 1 electron (9 protons + 1 electron = 10 electrons)
- \( Na^{+} \): Loses 1 electron (11 protons - 1 electron = 10 electrons)
- \( Mg^{2+} \): Loses 2 electrons (12 protons - 2 electrons = 10 electrons)
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