Properties of sulfur trioxide

Thermophysical properties for sulfur trioxide (CAS: 7446-11-9). 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
    O: 3, S: 1
  • CAS
    7446-11-9
  • Formula
    O3S
  • ID
    7446-11-9
  • InChI
    O3S/c1-4(2)3
  • InChI Key
    AKEJUJNQAAGONA-UHFFFAOYSA-N
  • IUPAC Name
    sulfur trioxide
  • Molecular Weight (kg)
    80.0632
  • Phase
    s
  • PubChem ID
    2.4682e+4
  • SMILES
    O=S(=O)=O
  • Synonyms

Physical Properties

  • Acentric factor
    0.4121
  • Critical pressure (bar)
    82.0733
  • Critical temperature (°C)
    217.85
  • Critical volume (m³/kmol)
    0.13
  • Dipole moment
    0
  • Melting temperature (°C)
    28.175
  • Normal boiling temperature (°C)
    44.5

State-dependent Properties

  • API gravity
    -58.6687
  • Compressibility factor
    0.00154622
  • Density (kg/m³)
    2116.45
  • Dynamic viscosity (cP)
    0
  • Enthalpy of vaporization (mass) (kJ)
    540.48
  • Enthalpy of vaporization (molar) (kJ/kmol)
    4.3273e+4
  • Gibbs free energy (kJ/kmol)
    0
  • Joule–Thomson coefficient
  • Kinematic viscosity
  • Molar enthalpy (kJ/kmol)
    0
  • Molar entropy (kJ/(kmol·K))
    0
  • Molar heat capacity (kJ/(kmol·K))
    39.3569
  • Molar volume (m³/kmol)
    0.037829
  • Parachor
    1.7984e-5
  • Poynting correction factor
    1.00113
  • Prandtl number
  • Saturation pressure (bar)
    0.350304
  • Saturation temperature (°C)
    44.5494
  • Solubility parameter
    3.1131e+4
  • Specific enthalpy (kJ)
    0
  • Specific entropy (kJ/kg·K)
    0
  • Specific gravity
    2.11854
  • Specific heat capacity (kJ/kg·K)
    0.491573
  • Surface tension
    0.0330908
  • Thermal conductivity
  • Thermal diffusivity

Safety Properties

  • Autoignition temperature (°C)
    -273.15
  • Flash point temperature (°C)
    -273.15
  • Lower flammability limit
    -0.197957
  • Upper flammability limit
    0.245076

Environmental Properties

  • Global warming potential
  • Ozone depletion potential