The ionic radii of K+, Na+, Al3+ and Mg2+ are in the order:
Solution
Al<sup>3+</sup>, Mg<sup>2+</sup> and Na<sup>+</sup> are isoelectronic ionic species. For monoatomic ionic isoelectronic species as positive charge increases ionic size decreases.<br><br>The order of size of Na<sup>+</sup> & K<sup>+</sup> is Na<sup>+</sup> < K<sup>+</sup><br><br>$\therefore$ Order of ionic radii is : Al<sup>3+</sup> < Mg<sup>2+</sup> < Na<sup>+</sup> < K<sup>+</sup>
About this question
Subject: Chemistry · Chapter: Periodic Table and Periodicity · Topic: Periodic Trends
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