The electron pair geometry around the central iodine in I3- is trigonal bipyramidal.
The shapes of molecules is determined by the Valence Shell Electron Pair Repulsion theory (VSEPR). According to this theory, The shape of a molecule depends on the number of electron pairs that surround the valence shell of the central atom in the molecule.
In the structure I3-, the iodine is sp3d hybridized and has a bond angle of 180°. There are three iodine atoms. The central iodine atom is surrounded by two bond pairs and three lone pairs. The electron pair geometry around the central iodine in I3- is trigonal bipyramidal.
Learn more: https://brainly.com/question/8646601