| ammonium bifluoride [ǝ`mōn·yǝm bī`flu̇r´īd] INORGANIC CHEMISTRY NH4F·HF A salt that crystallizes in the orthorhombic system and is soluble in water; prepared in the form of white flakes from ammonia treated with hydrogen fluoride; used in solution as a fungicide and wood preservative. Also known as ammonium acid fluoride; ammonium hydrogen fluoride. |