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Which of the following pairs represents isoelectronic ions?

Options

  1. ANa ⁺, K ⁺
  2. BK ⁺, Mg ²⁺
  3. CMg ²⁺, Ca ²⁺
  4. DCa ²⁺, S ²⁻

Correct answer

D. Ca ²⁺, S ²⁻

Step-by-step solution

aligned & Ca ²⁺ Number of electrons =20-2=18 & ~S ²⁻ Number of electrons =16+2=18 aligned

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