Reaction of tantalum with air
Tantalum does not react with air under normal conditions. The surface of tantalum metal can be protected by a thin layer of oxidation.
Tantalum reacts with water
Because the metal surface is protected by an oxidized film, tantalum will not react with water under normal conditions.
Tantalum reacts with halogens
Tantalum reacts with halogens when heated to form tantalum halide (V). Tantalum reacts with fluorine, F2, chlorine, Cl2, bromobr2 and iodide I2 to form tantalum bromide (V), TaF5, tantalum chloride (V), TaCl5, tantalum bromide (V), TaBr5 and tantalum iodide, respectively.
2Ta (s) + 5F2 (g) →TaF5 (s) [white]
2Ta (s) + 5Cl2 (g) →TaCl5 (l) [white]
2Ta (s) + 5Br2 (g) →TaBr5 (s) [light yellow]
2Ta (s) + 5I2 (g) →TaI5 (s) [Black]
Tantalum reacts with acid
Tantalum is not attacked by acid at room temperature, but is soluble in hydrofluoric acid, HF, or fuming sulfuric acid (a solution of sulfur trioxide SO3 in sulfuric acid H2SO4, also known as fuming sulfuric acid).
Tantalum and alkali reaction
Tantalum is attacked by molten alkali.
