Isobutane (data page) explained

This page provides supplementary chemical data on isobutane.

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 SIRI, and follow its directions.

Structure and properties

Structure and properties
Index of refraction, nD?
Abbe number?
Dielectric constant, εr? ε0 at ? °C
Bond strength?
Bond length?
Bond angle?
Magnetic susceptibility?
Surface tension10.3 dyn/cm at 20°C
    P 300 kPa

Thermodynamic properties

Phase behavior
Triple point113.55K (–159.6 °C), 0.019481 Pa
Critical point407.7 K (134.6 °C), 3650 kPa
Std enthalpy change
of fusion
, ΔfusHo
4.54 kJ/mol
Std entropy change
of fusion
, ΔfusSo
39.92 J/(mol·K)
Std enthalpy change
of vaporization
, ΔvapHo
21.3 kJ/mol
Std entropy change
of vaporization
, ΔvapSo
81.46 J/(mol·K)
Solid properties
Std enthalpy change
of formation
, ΔfHosolid
? kJ/mol
Standard molar entropy,
Sosolid
? J/(mol K)
Heat capacity, cp? J/(mol K)
Liquid properties
Std enthalpy change
of formation
, ΔfHoliquid
? kJ/mol
Standard molar entropy,
Soliquid
200.79 J/(mol K)
Heat capacity, cp129.70 J/(mol K) –253°C to –13°C
Gas properties
Std enthalpy change
of formation
, ΔfHogas
–134.2 kJ/mol
Standard molar entropy,
Sogas
249.7 J/(mol K)
Enthalpy of combustion, ΔcHo–2869 kJ/mol
Heat capacity, cp95.21 J/(mol K) at 20°C
van der Waals' constants[1] a = 1304.1 L2 kPa/mol2
b = 0.1142 liter per mole

Vapor pressure of liquid

P in mm Hg 1 10 40 100 400 760 1520 3800 7600 15200 3040045600
T in °C –109.2 –86.4 –68.4 –54.1 –27.1 –11.7 7.5 39.0 68.8 99.5  —  —
Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.

Spectral data

UV-Vis
λmax? nm
Extinction coefficient, ε?
IR
Major absorption bands? cm-1
NMR
 
 
Other NMR data  
MS
Masses of
main fragments
 

References

  1. Lange's Handbook of Chemistry 10th ed, pp 1522-1524