What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?

Question

What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results? K I 3

Philoid · Accepted Answer

In KI_3, O.N. of Kis + 1. Hence, the average O.N. is

However, O.N. cannot be fractional. Therefore, we will have to consider the structure of KI₃ to find the oxidation states.

In KI₃ molecule, an atom of iodine forms a coordinate covalent bond with an iodine molecule.

Hence, in a KI₃ molecule, the O.N. of the two I atoms forming the I₂ molecule is 0, wherein the O.N. of the I atom forming the coordinate bond is -1.