Which of the following are isoelectronic species ?
Correct answer: D. F- Ne Na+
- A. H+ H H-
- B. Li+ Na+ K+
- C. C1- Br- I
- D. F- Ne Na+
Explanation
Isoelectronic species have the same number of electrons. F- has 9 + 1 = 10 electrons, Ne has 10 electrons, and Na+ has 11 - 1 = 10 electrons. Students may choose b because Li+, Na+ and K+ are all cations, but they have 2, 10 and 18 electrons respectively.
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