Properties of acetylene

Thermophysical properties for acetylene (CAS: 74-86-2). 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: 2, H: 2
  • CAS
    74-86-2
  • Formula
    C2H2
  • ID
    74-86-2
  • InChI
    C2H2/c1-2/h1-2H
  • InChI Key
    HSFWRNGVRCDJHI-UHFFFAOYSA-N
  • IUPAC Name
    ethyne
  • Molecular Weight (kg)
    26.0373
  • Phase
    g
  • PubChem ID
    6326
  • SMILES
    C#C
  • Synonyms

Physical Properties

  • Acentric factor
    0.178
  • Critical pressure (bar)
    59.882
  • Critical temperature (°C)
    35.15
  • Critical volume (m³/kmol)
    0.11325
  • Dipole moment
    0
  • Melting temperature (°C)
    -80.75
  • Normal boiling temperature (°C)
    -84.1496

State-dependent Properties

  • API gravity
    181.121
  • Compressibility factor
    1
  • Density (kg/m³)
    1.06425
  • Dynamic viscosity (cP)
    0.0103202
  • Enthalpy of vaporization (mass) (kJ)
    260.285
  • Enthalpy of vaporization (molar) (kJ/kmol)
    6777.11
  • Gibbs free energy (kJ/kmol)
    0
  • Joule–Thomson coefficient
    1.9230e-13
  • Kinematic viscosity
    9.6972e-6
  • Molar enthalpy (kJ/kmol)
    0
  • Molar entropy (kJ/(kmol·K))
    0
  • Molar heat capacity (kJ/(kmol·K))
    45.5409
  • Molar volume (m³/kmol)
    24.4654
  • Parachor
    1.0341e-5
  • Poynting correction factor
    0.897188
  • Prandtl number
    0.688227
  • Saturation pressure (bar)
    47.7193
  • Saturation temperature (°C)
    -84.9002
  • Solubility parameter
    8639.69
  • Specific enthalpy (kJ)
    0
  • Specific entropy (kJ/kg·K)
    0
  • Specific gravity
    0.898524
  • Specific heat capacity (kJ/kg·K)
    1.74906
  • Surface tension
    0.00103037
  • Thermal conductivity
    0.0262279
  • Thermal diffusivity
    1.4090e-5

Safety Properties

  • Autoignition temperature (°C)
    305
  • Flash point temperature (°C)
    -273.15
  • Lower flammability limit
    0.023
  • Upper flammability limit
    1

Environmental Properties

  • Global warming potential
  • Ozone depletion potential