From engeneringtoolbox.com 
 
    *  Ammonia Molecular weight : 17.03 g/mol 
    * Ammonia Melting point : -78oC 
    * Ammonia Latent heat of fusion (1,013 bar, at triple point) : 331.37 kJ/kg 
    * Ammonia Liquid Density (1.013 bar at boiling point) : 682 kg/m3 (250 K : 669 kg/m3) (300 K : 600 kg/m3) (400 K : 346 kg/m3) 
    * Ammonia Liquid Specific Heat Capacity (cp) (250 K : 4.52 kJ/kg.K) (300 K : 4.75 kJ/kg.K) (400 K : 6.91 kJ/kg.K) 
    * Ammonia Liquid/gas equivalent (1.013 bar and 15oC (59oF)) : 947 vol/vol 
    * Ammonia Liquid Dynamic Viscosity (250K : 245 106 Ns/m2) (300K : 141 106 Ns/m2) (400K : 38 106 Ns/m2) 
    * Ammonia Liquid Thermal Conductivity (250 K : 592 106 kW/m.K) (300 K : 477 106 kW/m.K) (400 K : 207 106 kW/m.K) 
    * Ammonia Boiling point (1.013 bar) : -33.5oC 
    * Ammonia Latent heat of vaporization (1.013 bar at boiling point) : 1371.2 kJ/kg 
    * Ammonia Vapor pressure (at 21oC or 70oF) : 8.88 bar 
    * Ammonia Critical point - Critical temperature : 132.4oC - Critical pressure : 112.8 bar 
    * Ammonia Gas Density (1.013 bar at boiling point) : 0.86 kg/m3 
    * Ammonia Gas Density (1.013 bar and 15oC (59oF)) : 0.73 kg/m3 
    * Ammonia Gas Compressibility Factor (Z) (the ratio of the actual volume of the gas to the volume determined according to the perfect gas law) (1.013 bar and 15oC (59oF)) : 0.9929 
    * Ammonia Gas Specific Gravity (air = 1) (1.013 bar and 21oC (70oF)) : 0.597 
    * Ammonia Gas Specific volume (1.013 bar and 21oC (70oF)) : 1.411 m3/kg 
    * Ammonia Gas Specific Heat Capacity at constant pressure (cp) (1.013 bar and 15oC (59oF)) : 0.037 kJ/(mol.K) 
    * Ammonia Gas Specific Heat Capacity at constant volume (cv) (1.013 bar and 15oC (59oF)) : 0.028 kJ/(mol.K) 
    * Ammonia Gas Ratio of Specific Heats (Gamma: cp/cv) (1.013 bar and 15oC (59oF)) : 1.309623 
    * Ammonia Gas Dynamic Viscosity (1.013 bar and 0oC (32oF)) : 0.000098 Poise 
    * Ammonia Gas Thermal conductivity (1.013 bar and 0oC (32oF)) : 22.19 mW/(m.K) 
    * Ammonia Gas Solubility in water (1.013 bar and 0oC (32oF)) : 862 vol/vol 
    * Ammonia Gas Autoignition temperature : 630oC