question_answer 1)

  Which of the following sets contain only isoelectronic ions? (a) \[\text{Z}{{\text{n}}^{\text{2+}}}\text{,C}{{\text{a}}^{\text{2+}}}\text{,G}{{\text{a}}^{\text{3+}}}\text{,A}{{\text{l}}^{\text{3+}}}\]                                                (b) \[{{\text{K}}^{\text{+}}}\text{,C}{{\text{a}}^{\text{2+}}}\text{,S}{{\text{c}}^{\text{3+}}}\text{,C}{{\text{l}}^{\text{-}}}\] (c) \[{{P}^{3-}},{{S}^{2-}},C{{l}^{-}},{{K}^{+}}\]                                                    (d) \[T{{i}^{4+}},Ar,C{{r}^{3+}},{{V}^{5+}}\]

Answer:

  (b, c) The ions having same number of electrons are called isoelectronic ions. \[{{K}^{+}},C{{a}^{2+}},S{{c}^{3+}},C{{l}^{-}}\] ions have 18 electrons each. \[{{P}^{3-}},{{S}^{2-}},C{{l}^{-}},{{K}^{+}}\] ions have 18 electrons each.