Predict the number of unpaired electrons in the [Fe(CN)₆]^3- ion. A) 0 B) 1 C) 3 D) 5 E) None of the above

Question

Quizplus · Accepted Answer

The coordination number of iron (Fe) in the given compound is six. Cyanide (CN-) and sulfide (S2-) ions are considered strong field ligands as they form a strong bond with the Fe metal center, causing pairing of electrons in the d orbital. Based on this, we can conclude that all the six electrons of Fe would be paired with respective electrons of ligand CN-. 
Therefore, there will be one unpaired electron from the lone electron present on the sulfur (S) atom. Thus, the total number of unpaired electrons in the given compound is one. Hence, the correct answer is choice B.

Predict the Number of Unpaired Electrons in the [Fe(CN)6]3- Ion

Predict the Number of Unpaired Electrons in the [Fe(CN)₆]^3- Ion