CHEMICAL AND PHYSICAL PROPERTIES
| Physical Description | Isobutane is a colorless gas with a faint petroleum-like odor. It is shipped as a liquefied gas under its vapor pressure. Contact with the liquid can cause frostbite. It is easily ignited. The vapors are heavier than air. Any leak can either be liquid or vapor. It can asphyxiate by the displacement of air. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket. |
|---|---|
| Color/Form | Colorless gas [Note: Shipped as a liquified compressed gas. A liquid below 11 °F] |
| Odor | Gasoline-like or natural gas odor. |
| Boiling Point | 10.8 °F at 760 mmHg (USCG, 1999) |
| Melting Point | -427.5 °F (USCG, 1999) |
| Flash Point | -117 °F (USCG, 1999) |
| Solubility | Slight (NIOSH, 2023) |
| Density | 0.557 at 68 °F (USCG, 1999) - Less dense than water; will float |
| Vapor Density | 2.06 (NIOSH, 2023) - Heavier than air; will sink (Relative to Air) |
| Vapor Pressure | 3.1 atm at 70 °F (NIOSH, 2023) |
| LogP | log Kow = 2.76 |
| Stability/Shelf Life | Stable under recommended storage conditions. |
| Autoignition Temperature | 890 °F (USCG, 1999) |
| Decomposition | When heated to decomposition it emits acrid smoke and irritating fumes. |
| Viscosity | 0.238 cP at -10 °C |
| Corrosivity | No corrosive action on metals. |
| Heat of Combustion | -680.84 kcal/mol at 25 °C (liquid); -685.71 kcal/mol at 25 °C (gas) |
| Heat of Vaporization | 4.570 kcal/mol at 25 °C |
| Surface Tension | 14.1 dyne/cm at -10 °C |
| Ionization Potential | 10.74 eV |
| Refractive Index | Index of refraction: 1.3518 at 25 °C/D |
| Kovats Retention Index | 354.2 353.99 353.53 353.53 353 354 366 361.1 362 366 365 365 369 359 354 354 366 354.8 362 366 354.2 372.8 368 354 364 354.2 354 354 366 366 355 354 370 366 370 368 364 |
| Other Experimental Properties | Heat capacity at constant pressure = 23.10 cal/K-mol at 25 °C |
| Chemical Classes | Solvents -> Aliphatics, Saturated (<C12) |
SAFETY INFORMATION
| Signal word | Danger |
|---|---|
| Pictogram(s) |
 Flame Flammables GHS02  Gas Cylinder Compressed Gases GHS04 |
| GHS Hazard Statements |
H220:Flammable gases H280:Gases under pressure |
| Precautionary Statement Codes |
P410+P403:Protect from sunlight. Store in a well-ventilated place. |
COMPUTED DESCRIPTORS
| Molecular Weight | 58.12 g/mol |
|---|---|
| XLogP3 | 2.1 |
| Hydrogen Bond Donor Count | 0 |
| Hydrogen Bond Acceptor Count | 0 |
| Rotatable Bond Count | 0 |
| Exact Mass | 58.078250319 g/mol |
| Monoisotopic Mass | 58.078250319 g/mol |
| Topological Polar Surface Area | 0 Ų |
| Heavy Atom Count | 4 |
| Formal Charge | 0 |
| Complexity | 4.8 |
| Isotope Atom Count | 0 |
| Defined Atom Stereocenter Count | 0 |
| Undefined Atom Stereocenter Count | 0 |
| Defined Bond Stereocenter Count | 0 |
| Undefined Bond Stereocenter Count | 0 |
| Covalently-Bonded Unit Count | 1 |
| Compound Is Canonicalized | Yes |
PRODUCT INTRODUCTION
description
Isobutane is a colorless gas with a faint petroleum-like odor. It is shipped as a liquefied gas under its vapor pressure. Contact with the liquid can cause frostbite. It is easily ignited. The vapors are heavier than air. Any leak can either be liquid or vapor. It can asphyxiate by the displacement of air. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket.