UN No.: 2031 pH: (H2O, 20°C) strongly acid Solubility: (20°C) soluble Melting Point: -32°C Boiling Point: 121°C (1013 hPa) Vapor Pressure: 9.4 hPa (20°C) Density: 1.39 g/cm3 (20°C) Ignition Point: (H2O, 20°C) strongly acid