The given compound is iron carbonyl, represented as Fe(CO)5. In order to determine whether the compound is mononuclear, dinuclear, trinuclear, or tetranuclear, we must first understand the composition and structure of this compound.
Iron carbonyl, Fe(CO)5, is a type of metal carbonyl compound. Metal carbonyls are complexes in which metal atoms are bonded to carbon monoxide (CO) ligands.
Structure of Fe(CO)5:
- The molecular formula Fe(CO)5 indicates that there is one iron (Fe) atom and five carbon monoxide (CO) ligands in the complex.
- In Fe(CO)5, the single iron atom is bonded to five CO ligands, forming a coordination complex.
- Structurally, Fe(CO)5 has a trigonal bipyramidal geometry due to the spatial arrangement of the five CO ligands around the central iron atom.
Understanding the term "Mononuclear":
- The term "mononuclear" refers to a complex that contains exactly one central metal atom or ion.
- In Fe(CO)5, since there is only one iron atom present, it is mononuclear.
Conclusion:
Given the structure and composition of Fe(CO)5, it is clear that the complex is mononuclear as it contains only one central iron atom bonded to five carbon monoxide ligands.
Answer: The correct option is mononuclear.