Rank the following ions in order of decreasing ionic radius: S^2-,O^2-,F^-,Na⁺,Mg²⁺. A)S^2-,O^2-,F^-,Na⁺,Mg²⁺ B)O^2-,F^-,Na⁺,Mg²⁺,S^2- C)O^2-,S^2-,F^-,Na⁺,Mg²⁺ D)Mg²⁺,Na⁺,F^-,O^2-,S^2- E)Mg²⁺,S^2-,Na⁺,F^-,O^2-

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Ionic radius decreases across a period due to increasing nuclear charge, causing electrons to be pulled closer to the nucleus. It increases down a group as additional electron shells are added. The given ions, when translated from their coded form, are S^2-, O^2-, F^-, Na^+, and Mg^2+. S^2- is the largest because it is the furthest down the group and has gained electrons, making its radius larger. O^2- is next, being in the same group but one period above S^2-. F^- is smaller than O^2- because it has one less electron. Na^+ and Mg^2+ are cations and are smaller than the anions due to loss of electrons and increased effective nuclear charge, with Mg^2+ being the smallest because it has lost two electrons and is from the same period as Na^+.

Rank the Following Ions in Order of Decreasing Ionic Radius