Properties of Isobutane (C4H10)

Isobutane, also known as methylpropane, is a chemical compound with the molecular formula C4H10. It is a colorless, flammable gas at room temperature and is commonly used as a fuel, refrigerant, or propellant in aerosol sprays.

The following table provides a comprehensive list of isobutane 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.

Table of Isobutane Properties
Physical Properties
Metric
Molar Mass58.123 g/mol
Density (0°C)2.593 kg/m3
Dynamic Viscosity (25°C)7.5 µPa·s
Thermal PropertiesMetric
Melting Point-159.6 °C
Boiling Point-11.7 °C
Thermal Conductivity (25°C)0.0171 W/m·K
Specific Heat Capacity (Cp)1662 J/kg·K
Critical ConstantsMetric
Critical Temperature (Tc)135 °C
Critical Pressure (Pc)3.65 MPa
Critical Density (ρc)221 kg/m3
Electrical PropertiesMetric
Relative Permittivity (εr)1.00268
Hazardous DataMetric
Autoignition Temperature460 °C
Lower Flammability Limit1.8%
Upper Flammability Limit8.5%
NFPA Rating (Health)1
NFPA Rating (Fire)4
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.