Properties of Ammonia (NH3)
Ammonia is a colorless and pungent gas with the chemical formula NH3. It is commonly used in various industrial processes, refrigeration, cleaning products, and agriculture as a fertilizer.
The following table provides a comprehensive list of ammonia properties in both SI and US customary/Imperial units at normal temperature and pressure (NTP).
Click on the icon to switch between Metric and Imperial units.
| Physical Properties | Metric |
|---|---|
| Molar Mass | 17.031 g/mol |
| Density (0°C) | 0.707 kg/m3 |
| Dynamic Viscosity (25°C) | 10.2 µPa·s |
| Speed of Sound in Gas (0°C) | 414 m/s |
| Thermal Properties | Metric |
| Melting Point | -77.7 °C |
| Boiling Point | -33.4 °C |
| Thermal Conductivity (25°C) | 0.0251 W/m·K |
| Specific Heat Capacity (Cp) | 2092 J/kg·K |
| Critical Constants | Metric |
| Critical Temperature (Tc) | 132.4 °C |
| Critical Pressure (Pc) | 11.28 MPa |
| Critical Density (ρc) | 235 kg/m3 |
| Electrical Properties | Metric |
| Relative Permittivity (εr) | 1.0072 |
| Optical Properties | Metric |
| Refractive Index (589 nm) | 1.000374 |
| Hazardous Data | Metric |
| Autoignition Temperature | 651 °C |
| Lower Flammability Limit | 15% |
| Upper Flammability Limit | 28% |
| NFPA Rating (Health) | 3 |
| NFPA Rating (Fire) | 1 |
| NFPA Rating (Reactivity) | 0 |
Unless stated otherwise, all values are taken at room temperature (approximately 20°C or 68°F) and 1 atm pressure. (1 atm = 101,325 Pa)
Related Pages
References: 1) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 2) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017. 3) Yaws, Carl L. The Yaws Handbook of Physical Properties for Hydrocarbons and Chemicals. Netherlands: Elsevier Science, 2015. 4) Fire Protection Guide to Hazardous Materials, 14th Edition. United States: National Fire Protection Association, 2010.