Butane (data page)

This page provides supplementary chemical data on n-butane.

Material Safety Data Sheet

The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source such as eChemPortal, and follow its directions.

Structure and properties

Structure and properties
Index of refraction, n_D	1.3326 at 20 °C
Dielectric constant, ε_r	1.7697 ε₀ at 23 °C
Symmetry group	C_2h
Magnetic susceptibility	?
Surface tension	12.46 dyn/cm at 20 °C P ≈ 225 kPa

Thermodynamic properties

Phase behavior
Density (liquid) 0 °C	600 kg/m³
Density (saturated vapor) 1 atm, -0.5 °C	2.6 kg/m³
Triple point	134.6 K (–138.5 °C), 0.7 Pa
Critical point	425.1 K (152.0 °C), 3796.0 kPa
Std enthalpy change of fusion, Δ_fusH^o	4.66 kJ/mol
Std entropy change of fusion, Δ_fusS^o	34.56 J/(mol·K)
Std enthalpy change of vaporization, Δ_vapH^o	22.44 kJ/mol
Std entropy change of vaporization, Δ_vapS^o	82.30 J/(mol·K)
Solid properties
Std enthalpy change of formation, Δ_fH^o_solid	? kJ/mol
Standard molar entropy, S^o_solid	? J/(mol K)
Heat capacity, c_p	? J/(mol K)
Liquid properties
Std enthalpy change of formation, Δ_fH^o_liquid	-147.6 kJ/mol
Standard molar entropy, S^o_liquid	229.7 J/(mol K)
Heat capacity, c_p	132.42 J/(mol K) –262 °C to –3 °C
Gas properties
Std enthalpy change of formation, Δ_fH^o_gas	–124.7 kJ/mol
Standard molar entropy, S^o_gas	310.23 J/(mol K)
Enthalpy of combustion, Δ_cH^o	–2877.5 kJ/mol
Heat capacity, c_p	98.49 J/(mol K) at 25 °C
n-butane van der Waals' constants	a = 1466.2 L² kPa/mol² b = 0.1226 liter per mole

Vapor pressure of liquid

P in mm Hg		1	10	40	100	400	760	1520	3800	7600	15200	30400	45600
T in °C		–101.5	–77.8	–59.1	–44.2	–16.3	–0.5	18.8	50.0	79.5	116.0	—	—

n-Butane: Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.

**Vapor pressure of n-butane**. From formula: $\scriptstyle \log _{10}P_{mmHg}=6.83029-{\frac {945.90}{240.0+T}}$ obtained from *Lange's Handbook of Chemistry*, 10th ed.

Spectral data

UV-Vis
λ_max	? nm
Extinction coefficient, ε	?
IR
Major absorption bands	? cm⁻¹
NMR
Proton NMR
Carbon-13 NMR
Other NMR data
MS
Masses of main fragments

References

"Multifunctional Green Alternative: Propane and Butane (properties)". Seminck. Archived from the original on 28 September 2007. Retrieved 1 May 2007.

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Except where noted otherwise, data relate to Standard temperature and pressure.
Reliability of data general note.