Question

In the coordination compound (NH4)2[Fe(OH2)F5], the Fe is octahedrally coordinated. (a) Based on the fact that F is a weak-field ligand, pre- dict whether this compound is diamagnetic or para- magnetic. If it is paramagnetic, tell how many unpaired electrons it has. (b) By comparison with other complexes reviewed in this chapter, discuss the likely color of this compound. (c) Determine the d-electron configuration of the iron in this compound. (d) Name this compound.

Answer 1

a) The compound is diamagnetic with no unpaired electrons. b) The specific color cannot be determined. c) The d-electron configuration is d6. d) The name of the compound is (NH4)2[Fe(OH2)F5].

Step-by-step explanation:

a) Diamagnetic compounds have all their electrons paired, while paramagnetic compounds have unpaired electrons. Since F- is a weak-field ligand, it will produce a small crystal field splitting, resulting in a lower energy t2g and higher energy eg orbitals. In this compound, the Fe2+ ion will have a d6 electron configuration. Since there are no unpaired electrons, the compound is diamagnetic.

b) The likely color of this compound can be determined by comparing it with other complexes with similar metal complexes. However, the specific color cannot be determined without conducting experiments.

c) The d-electron configuration of the iron in this compound will be d6, meaning there are six electrons in the d orbitals.

d) The name of this compound is (NH4)2[Fe(OH2)F5].