question_answer

The geometrical arrangement and shape of \[I_{3}^{-}\] are respectively

A)  trigonal bipyramidal geometry, linear shape

B)  hexagonal geometry, T-shape

C)  triangular planar geometry, triangular shape

D)  tetrahedral geometry, pyramidal shape

Correct Answer: A

Solution :

 \[I_{3}^{-}\Rightarrow 2\] 2 bond pairs + 3 lone pairs =5 hybrid orbitals. Thus, hybridisation is \[s{{p}^{3}}d\]and geometrical arrangement is trigonal bipyramidal.  However, its shape is linear because of the presence of three lone pairs of electrons.