Bromine - ₃₅Br: reactions of elements

Reaction of bromine with air

Bromine, Br₂ is not reactive towards with oxygen, O₂, or nitrogen, N₂. However, bromine does react with ozone, O₃, the second allotrope of oxygen, at -78°C to form the unstable dioxide bromine(IV) oxide, BrO₂.

Br₂(l) + 2O₃(g) → O₂(g) + 2BrO₂(s) [brown]

Reaction of bromine with water

Bromine, Br₂, reacts with water to produce hypobromite, OBr^-. The position of the equilibrium depends very much upon the pH of the solution.

Br₂(l) + H₂O(l) ⇌ OBr^-(aq) + 2H⁺(aq) + Br^-(aq)

Reaction of bromine with the halogens

Bromine, Br₂, reacts with fluorine, F₂, in the gas phase to form the interhalogen species BrF. The product is difficult to obtain pure since BrF disproportionates at room temperature to form bromine, Br₂, and BrF₃ and BrF₅.

Br₂(g) + F₂(g) → 2BrF(g)

3BrF(g) → Br₂(l) + BrF₃(l)

5BrF(g) → 2Br₂(l) + BrF₅(l)

Under more forcing conditions, excess fluorine reacts with bromine, Br₂, at 150°C to form the interhalogen species BrF₅.

Br₂(l) + 5F₂(g) → 2BrF₅(l)

Chlorine, Cl₂, reacts with bromine, Br₂, in the gas phase to form the unstable interhalogen species bromine(I) chloride, ClBr.

Cl₂(g) + Br₂(g) → 2ClBr(g)

Similarly, bromine, Br₂, reacts with iodine, I₂, at room temperature to form the interhalogen species bromine(I) iodide, BrI.

Br₂(l) + I₂(s) → 2IBr(s)

Reaction of bromine with acids

Reaction of bromine with bases

Bromine, Cl₂, reacts with hot aqueous alkali to produce bromate, BrO₃^-. Only one sixth of the total bromine is converted in this reaction.

3Br₂(g) + 6OH^-(aq) → BrO₃^-(aq) + 5Br^-(aq) + 3H₂O