Grade: ACS, ISO UN No.: UN2014 pH: 2 - 4 (H2O, 20°C) Solubility: (20°C) soluble Melting Point: -26°C Boiling Point: 107°C (1013 hPa) Vapor Pressure: 18 hPa (20°C) Density: 1.11 g/cm3 (20°C)