Properties of Propionic Acid (C3H6O2)
Propionic acid, also known as propanoic acid, is a simple organic compound with the chemical formula C3H6O2. It is a colorless, oily liquid with a pungent and unpleasant odor. Propionic acid is a carboxylic acid, and it is a naturally occurring compound found in various plant and animal tissues.
The following table provides a comprehensive list of propionic acid properties in both SI and US customary/Imperial units at normal temperature and pressure (NTP).
Click on the button to switch between Metric and Imperial units.
| Physical Properties | Metric |
|---|---|
| Molar Mass | 74.08 g/mol |
| Density | 990 kg/m3 |
| Dynamic Viscosity | 1.16 mPa·s |
| Surface Tension (15°C) | 27.21 mN/m |
| Thermal Properties | Metric |
| Melting Point | -21 °C |
| Boiling Point | 141.1 °C |
| Thermal Conductivity (25°C) | 0.144 W/m·K |
| Vapor Pressure | 0.33 kPa |
| Critical Constants | Metric |
| Critical Temperature (Tc) | 330 °C |
| Critical Pressure (Pc) | 4.5 MPa |
| Critical Molar Volume (Vc) | 232 cm3/mol |
| Electrical Properties | Metric |
| Relative Permittivity (εr) (25°C) | 3.44 |
| Optical Properties | Metric |
| Refractive Index (589 nm) | 1.385 |
| Hazardous Data | Metric |
| Flash Point | 52 °C |
| Autoignition Temperature | 465 °C |
| Lower Flammability Limit | 2.9% |
| Upper Flammability Limit | 12.1% |
| NFPA Rating (Health) | 3 |
| NFPA Rating (Fire) | 2 |
| 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)
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.