HBr, or hydrobromic acid, is classified as a strong electrolyte. This classification arises from its ability to completely ionize in aqueous solution, meaning that when HBr is dissolved in water, it separates into hydrogen ions (H+) and bromide ions (Br–) nearly completely. Consequently, solutions of HBr conduct electricity very well due to the high concentration of free-moving ions.
In contrast, weak electrolytes partially ionize in solution, resulting in a mixture of ions and un-ionized molecules, leading to poor conductivity. Nonelectrolytes, on the other hand, do not ionize at all in solution, which also results in no electrical conductivity. Therefore, given that HBr fully dissociates in water, it is appropriately identified as a strong electrolyte.