The following are isoelectronic ions except
-
A.
Na(^+) -
B.
Mg(^{2+}) -
C.
Si(^{2+}) -
D.
O(^{2+})
Correct Answer: Option C
Explanation
Two or more ions are said to be isoelectronic if they have the same electronic structure and the same number of valence electrons.
Na(^+) = 10 electrons = 2, 8
Mg(^{2+}) = 10 electrons = 2,8
O(^{2-}) = 10 electrons = 2,8
Si(^{2+}) = 12 electrons = 2,8,2
(implies) Si(^{2+}) is not isoelectronic with the rest.
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