question_answer

The correct structure of \[Fe{{(CO)}_{5}}\] is : [AIPMT 2000]

A) trigonal bipyramidal

B) octahedral

C) tetrahedral

D) square pyramidal

Correct Answer: A

Solution :

[a] In, \[Fe{{(CO)}_{5}},\] the Fe atom is in \[ds{{p}^{3}}\] hybridised state. Therefore, the shape of molecule is trigonal bipyramidal. The hybridisation is as

\[_{26}Fe=1{{s}^{2}},\,\,2{{s}^{2}}\,2{{p}^{6}},\,3{{s}^{2}}\,3{{p}^{6}}\,3{{p}^{6}},\,4{{s}^{2}}\,4{{p}^{0}}\]

In \[Fe{{(CO)}_{5}}\] the \['Fe'\] atom is -