Lewis structure of Hydrogen iodide (HI) contains only one H-Br bond. There are no charges on atoms in HI lewis structure because HI is a neutral molecule. There is three lone pairs on bromine atom in HI molecule. HI is a very easy lewis structure to draw due to its simplicity.
There are only one hydrogen atom and one iodine atom in HI molecule. In the lewis structure of HI, hydrogen atom has made a single bond with iodine atom.
When we draw a lewis structure, there are several steps to follow. Number of steps can be changed according the complexity of the molecule or ion. Because HI molecule is a simple, and there is no overall charge, all of these steps are not required to use to complete the lewis structure. However those all steps are mentioned and explained in detail in this tutorial for your knowledge.
There are two elements in hydrogen iodide; hydrogen and iodine. Hydrogen is a group IA element in the periodic table and only has one electron in its last shell (valence shell). Iodine is a group VIIA element in the periodic table and contains seven electrons in its last shell. Now, we know how many electrons are there in valence shells of hydrogen and bromine atoms.
Total valance electrons pairs = σ bonds + π bonds + lone pairs at valence shells
Total electron pairs are determined by dividing the number total valence electrons by two. For, HI, Total pairs of electrons are four in their valence shells.
Because, there are only two elements in HI molecule, we do not need to worry about finding the center atom. Therefore, we can draw the skeleton of HI easily.
After determining the center atom and sketch of HI molecule, we can start to mark lone pairs on atoms. Remember that, there are total of four electron pairs.
There are no charges on hydrogen atom and iodine atom. Also, remember that HI is a molecule which does not have a charge. Therefore, not having charges on every atoms tells us we have drawn a stable structure.
Because there are no charges on atoms, no need to worry about reducing charges as a step of obtaining the best lewis structure. Therefore, we have already got the best lewis structure for HI.