Why does chlorine react with hydrogen bromide?

Chlorine reacts with hydrogen bromide because it is more reactive than bromine, allowing it to displace bromine from the compound. In this reaction, chlorine, a halogen, can take the place of bromine in hydrogen bromide due to its higher reactivity. The order of reactivity of halogens is critical to understanding this reaction: fluorine is the most reactive, followed by chlorine, then bromine, and finally iodine. When chlorine gas is introduced to hydrogen bromide, it leads to the formation of hydrogen chloride and bromine, demonstrating its ability to displace bromine. This reactivity is a characteristic behavior of halogens in displacement reactions, showcasing how a more reactive halogen can substitute for a less reactive one in a compound.