<unk>  is a reactive gas with the chemical formula . It has a characteristic sweet odor that resembles gasoline and kerosene. It is toxic and is a powerful oxidizing and fluorinating agent. It is the acid fluoride of perchloric acid. In spite of its small enthalpy of formation (ΔHf° = −5.2 kcal/mol), it is kinetically stable, decomposing only at 400 °C. It is quite reactive towards reducing agents and anions, however, with the chlorine atom acting as an electrophile. It reacts explosively with reducing agents such as metal amides, metals, hydrides, etc. Its hydrolysis in water occurs very slowly, unlike that of chloryl fluoride.
Perchloryl fluoride
Silver diammine fluoride
Amine fluoride
Arsenic trichloride
Amylmetacresol
Sodium fluoride
Silver nitrate
Dichloroacetic acid