Answer:
The hybrid orbitals involved are sp3d2
The bond angle is less than 90°
Explanation:
In ICl5, hybridization of the central iodine atom is sp3d2. Knowing that iodine has one pair of unshared electrons in the hybrid orbitals and it is bonded to 5 chlorine atoms in the compound, the most stable configuration, minimizing the repulsion between the pair of electrons and the electrons from the chemical bonds is a square pyramidal arrangement with bond angle less than 90°.
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