Which has the greater number of unpaired electrons? I. square planar Ni(CN)₄^2- II. tetrahedral FeCl₄^- A) I B) II C) Neither I nor II has any unpaired electrons. D) More information is needed. E) Both I and II have the same (nonzero) number of unpaired electrons.

Question

Quizplus · Accepted Answer

Tetrahedral FeCl4 has more unpaired electrons because Fe in a tetrahedral complex typically has a high spin configuration, leading to unpaired electrons. Square planar Ni(CN)4, on the other hand, is usually low spin with paired electrons due to the strong field ligand CN-, resulting in fewer (or no) unpaired electrons.

Which Has the Greater Number of Unpaired Electrons