Hexane

Hexane

n-Hexane bottle and a small sample
Names
IUPAC name Hexane
Other names n-Hexane
Identifiers
Jmol-3D images	Image
SMILES CCCCCC
Properties
Chemical formula	C6H14
Molar mass	86.18 g/mol
Appearance	Colorless liquid
Odor	Gasoline-like
Density	0.6548 g/ml
Melting point	−96 to −94 °C (−141 to −137 °F; 177 to 179 K)
Boiling point	68.5 to 69.1 °C (155.3 to 156.4 °F; 341.6 to 342.2 K)
Solubility in water	9.5 mg/L
Solubility	Miscible with ethanol
Vapor pressure	17.60 kPa (at 20.0 °C)
Thermochemistry
Std molar entropy (So298)	296.06 J K−1 mol−1
Std enthalpy of formation (ΔfHo298)	−199.4–−198.0 kJ mol−1
Hazards
Safety data sheet	LabChem
Flash point	−26.0 °C
Lethal dose or concentration (LD, LC):
LD50 (Median dose)	25 g/kg (oral, rat) 28710 mg/kg (rat, oral)
LC50 (Median concentration)	56137 mg/kg (rat, oral)
Related compounds
Related compounds	Pentane Heptane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Hexane or n-hexane is an alkane, containing six carbon atoms, with the chemical formula C₆H₁₄.

Properties

Chemical

Hexane will burn in air when ignited:

C₆H₁₄ + 19/2 O₂ → 6 CO₂ + 7 H₂O + heat

Hexane will react with bromine under UV light to yield bromohexane.

Physical

Hexane is a colorless liquid, with a petrolic odor, similar to lighter fluid. It is insoluble in water, but miscible with many organic solvents. It has a melting point of −95.3 °C and a boiling point of 68.7 °C. Hexane has considerable vapor pressure at room temperature (121.26 mmHg). It has a density of 0.6548 g/ml. Hexane is flammable, with a flash point of −26.0 °C and an autoignition temperature of 234.0 °C.

Availability

Certain lighter fluids contain n-hexane.

Stoddard solvent contains n-hexane along other alkanes, which can be separated via fractal distillation. However this may require large amounts of solvent.

Some rubber cements contain hexane as solvent, though not all.

Preparation

Hexane can be extracted by fractual distillation of gasoline, though this process is intense and time-consuming.

Projects

• Extract oils from plants
• Chemical reaction medium for organometallic reactions
• N-buthyllithium storage

Handling

Safety

Hexane is irritant to the nose and eyes. The acute toxicity of n-hexane is rather low, however it can be metabolized by the organism to hexane-2,5-dione which is toxic. Long term exposure poses a health hazard. It's suspected to cause disruptions to the reproductive system.

Storage

Hexane must be stored in closed bottles, away from any heat or light source. Due to its high vapor pressure, it's mandatory to keep the bottle open or semi-open after being moved from a cold area to a warmer one, to prevent a dangerous build-up of pressure, until the entire content of the bottle reaches the room temperature.

Disposal

Hexane can be safely burned as it only releases carbon oxides and water vapor and extremely little soot.

References

Relevant Sciencemadness threads

• Obtaining Hexane (Down-under)
• Effectiveness of hexane as a solvent for benzaldehyde.