Total number of lone pair of electrons in ${\mathrm{I}}_3^{-}$ ion is-----

It has an atomic number 53
It has an electronic configuration [Kr]5s² 4d¹⁰ 5p²
As it has one negative charge also present on it so total electrons will be 22
, and have 11 pair of electrons.
There are two bonds between three Iodine atoms and electrons are used for making bonds 4
.
Number of electrons remaining is 18
Lone pairs present in triiodide is 9
It has SP³d² hybridization.
Its shape bent shape for minimizing the repulsion between lone pairs.