According to periodic trends, arrange the following ions, potassium, magnesium, and aluminum in order of increasing ionic size.

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Ionic size increases as you move down a group in the periodic table because each element down the group has an additional electron shell compared to the one above it. Potassium (K) is below both magnesium (Mg) and aluminum (Al) in the periodic table, so its ion will be larger than either Mg or Al ions. Between magnesium and aluminum, which are in the same period with magnesium to the left of aluminum, the Mg ion will be larger because it loses fewer electrons to achieve a noble gas configuration, resulting in a less significant reduction in size due to decreased electron-electron repulsion. Therefore, the order of increasing ionic size is aluminum ion, magnesium ion, and potassium ion.

According to Periodic Trends, Arrange the Following Ions, Potassium, Magnesium