Astatine

Astatine dissolves in dilute nitric acid, HNO₃, and dilute hydrochloric acid, HCl.

Astatine, At₂, reacts with bromine, Br₂, or iodine, I₂, forming AtBr and AtI respectively.

At₂ + Br₂ 2 AtBr
At₂ + I₂ 2 AtI