Properties of isobutyric acid

Thermophysical properties for isobutyric acid (CAS: 79-31-2). Use the selector below to view properties in different unit systems.

Calculation Conditions

The following state-dependent properties were calculated at these standard conditions.

Temperature

25 °C

Pressure

1.01325 bar

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Identification

  • Atoms
    C: 4, H: 8, O: 2
  • CAS
    79-31-2
  • Formula
    C4H8O2
  • ID
    79-31-2
  • InChI
    C4H8O2/c1-3(2)4(5)6/h3H,1-2H3,(H,5,6)
  • InChI Key
    KQNPFQTWMSNSAP-UHFFFAOYSA-N
  • IUPAC Name
    2-methylpropanoic acid
  • Molecular Weight (kg)
    88.1051
  • Phase
    l
  • PubChem ID
    6590
  • SMILES
    CC(C)C(=O)O
  • Synonyms

Physical Properties

  • Acentric factor
    0.61
  • Critical pressure (bar)
    37
  • Critical temperature (°C)
    331.85
  • Critical volume (m³/kmol)
    0.29
  • Dipole moment
    1.09
  • Melting temperature (°C)
    -46
  • Normal boiling temperature (°C)
    154.4

State-dependent Properties

  • API gravity
    16.8878
  • Compressibility factor
    0.00381469
  • Density (kg/m³)
    944.038
  • Dynamic viscosity (cP)
    1.2248
  • Enthalpy of vaporization (mass) (kJ)
    404.609
  • Enthalpy of vaporization (molar) (kJ/kmol)
    3.5648e+4
  • Gibbs free energy (kJ/kmol)
    0
  • Joule–Thomson coefficient
    -3.8949e-7
  • Kinematic viscosity
    1.2974e-6
  • Molar enthalpy (kJ/kmol)
    0
  • Molar entropy (kJ/(kmol·K))
    0
  • Molar heat capacity (kJ/(kmol·K))
    170.192
  • Molar volume (m³/kmol)
    0.093328
  • Parachor
    3.7023e-5
  • Poynting correction factor
    1.00382
  • Prandtl number
    16.9938
  • Saturation pressure (bar)
    0.00184437
  • Saturation temperature (°C)
    154.425
  • Solubility parameter
    1.8852e+4
  • Specific enthalpy (kJ)
    0
  • Specific entropy (kJ/kg·K)
    0
  • Specific gravity
    0.944967
  • Specific heat capacity (kJ/kg·K)
    1.93169
  • Surface tension
    0.0243906
  • Thermal conductivity
    0.139224
  • Thermal diffusivity
    7.6346e-8

Safety Properties

  • Autoignition temperature (°C)
    443
  • Flash point temperature (°C)
    58
  • Lower flammability limit
    0.02
  • Upper flammability limit
    0.1

Environmental Properties

  • Global warming potential
  • Ozone depletion potential