فلوريد الهيدروجين
HF is miscible with water (dissolves in any proportion). In contrast, the other hydrogen halides exhibit limiting solubilities in water. Hydrogen fluoride forms a monohydrate HF.H2O with m.p.−40 °C (−40 °F), which is 44 °C (79 °F) above the melting point of pure HF.