Molecular weight (g/mol) 72.58 Boiling point (101.3kpa c) -51.6 Critical temperature , â°c 72.5 Critical pressure , mpa 4.95 Density of liquid at 30 â°c, g/cm3 1.038 Sepecific heat of liquid 30â°c, 0.29 Sepecific heat of equipressure steam(cp), 30â°c and 101.3kpa 0.85 Vaporization heat under b.P., kj/kg 220.0 Odp 0