To draw a Lewis dot structure for sulfur dibromide (SBr2), write an S to represent sulfur with a Br for bromine on either side of it, and then put two dots on the top, bottom and either side of these three elements to represent the valence electrons. On the periodic table, bromine is a group seven element, sometimes called 17 while sulfur is a group six element, sometimes known as 16. This means that the valence electrons in bromine atom are seven while those of sulfur are six.
The total valence electrons of bromine atoms in sulfur dibromide should be 14 because they are two, and the overall number of valence electrons should be (14 + 6), which is 20 electrons. Sulfur should come in the middle because it is the least electronegative, and the bromine atoms should be on each side of the sulfur atom. These 20 valence electrons should be appropriately distributed around the molecule to form the Lewis structure.
When a pair of electrons is put between the atoms to form covalent bonds, four electrons will be used. The remaining 16 electrons should be distributed on the outside of each atom whereby sulfur should get two pairs, and each of the bromine atoms should get three pairs, giving a total of 16 electrons. Therefore, each of the bromine atoms should have eight valence electrons meaning that their outer shells are full. The outer shell of sulfur should also be full with eight valence electrons.