title: O-Xylene (data page)
text: # O-Xylene (data page)
  
  This page provides supplementary chemical data on o-Xylene.
  
  ## 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. MSDS is available from MATHESON TRI-GAS, INC. in the SDSdata.org database.
  
  ## Structure and properties
  
  Structure and properties :
  
  | Index of refraction, $n_D$ | 1.5058 at 20°C |
  | - | - |
  | Abbe number | ? |
  | Dielectric constant, $ε_r$ | 2.568 $ε_0$ at 20 °C |
  | Bond strength | ? |
  | Bond length | ? |
  | Bond angle | ? |
  | Magnetic susceptibility | ? |
  | Surface tension | 30.10 dyn/cm at 20°C |
  | Viscosity | 1.1049 mPa·s at 0°C 0.8102 mPa·s at 20°C 0.6270 mPa·s at 40°C 0.4168 mPa·s at 80°C 0.2626 mPa·s at 140°C |
  | Solubility | 0.171 g/L at 25°C 0.21 g/L at 45°C |
  
  ## Thermodynamic properties
  
  Phase behavior :
  
  | Triple point | 247.8 K (−25.3 °C), ? Pa |
  | - | - |
  | Critical point | 631 K (358 °C), 3700 kPa |
  | Std enthalpy change of fusion, $Δ_{fus}H^o$ | 13.6 kJ/mol |
  | Std entropy change of fusion, $Δ_{fus}S^o$ | 54.87 J/(mol·K) at −25.3 |
  | Std enthalpy change of vaporization, $Δ_{vap}H^o$ | 36.24 kJ/mol at 144.5°C |
  | Std entropy change of vaporization, $Δ_{vap}S^o$ | ? 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, $Δ_fH^o_{liquid}$ | −24.4 kJ/mol |
  | Standard molar entropy, $S^o_{liquid}$ | 247 J/(mol K) |
  | Enthalpy of combustion, $Δ_cH^o$ | −4552 kJ/mol |
  | Heat capacity, $c_p$ | 187.0 J/(mol K) at 25°C |
  | Gas properties ||
  | Std enthalpy change of formation, $Δ_fH^o_{gas}$ | 19.0 kJ/mol |
  | Standard molar entropy, $S^o_{gas}$ | 353.6 J/(mol K) |
  | Heat capacity, $c_p$ | 132.5 J/(mol K) at 25°C |
  | van der Waals' constants | a = 3038 $L^2$ $kPa/mol^2$ b = 0.1755 liter per mole |
  
  ## Vapor pressure of liquid
  
  | P in mm Hg | P in mm Hg | 1 | 10 | 40 | 100 | 400 | 760 |
  | - | - | - | - | - | - | - | - |
  | T in °C | T in °C | −3.8 | 32.1 | 59.5 | 81.3 | 121.7 | 144.4 |
  
  Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.
  
  ## Distillation data
  
  See also:
  
  * m-xylene (data page)
  * p-xylene (data page)
  
  Vapor-liquid Equilibrium for o-Xylene/m-Xylene P = 26.66 kPa :
  
  | BP Temp. °C | % by mole m-xylene | % by mole m-xylene |
  | - | - | - |
  | BP Temp. °C | liquid | vapor |
  | 100.1 | 0.0 | 0.0 |
  | 99.8 | 4.7 | 5.6 |
  | 99.6 | 9.7 | 11.4 |
  | 99.2 | 17.8 | 20.6 |
  | 98.8 | 25.9 | 29.3 |
  | 98.4 | 34.1 | 38.1 |
  | 97.9 | 42.5 | 46.8 |
  | 97.6 | 49.6 | 53.9 |
  | 97.2 | 57.4 | 61.5 |
  | 96.8 | 65.5 | 69.2 |
  | 96.5 | 73.5 | 76.5 |
  | 96.1 | 80.8 | 83.2 |
  | 95.8 | 88.6 | 90.2 |
  | 95.6 | 93.7 | 94.6 |
  | 95.3 | 100.0 | 100.0 |
  
  Vapor-liquid Equilibrium for o-Xylene/Carbon tetrachloride P = 760 mm Hg :
  
  | BP Temp. °C | % by mole carbon tetrachloride | % by mole carbon tetrachloride |
  | - | - | - |
  | BP Temp. °C | liquid | vapor |
  | 142.0 | 1.8 | 6.5 |
  | 136.0 | 6.4 | 22.9 |
  | 130.4 | 11.2 | 36.9 |
  | 125.0 | 16.1 | 49.4 |
  | 120.7 | 20.4 | 57.3 |
  | 116.1 | 25.3 | 64.6 |
  | 111.8 | 30.2 | 70.9 |
  | 107.9 | 35.2 | 75.9 |
  | 104.2 | 40.4 | 80.3 |
  | 104.1 | 40.5 | 80.5 |
  | 99.4 | 47.8 | 85.2 |
  | 95.1 | 55.4 | 88.9 |
  | 91.6 | 62.4 | 91.6 |
  | 88.2 | 70.0 | 94.0 |
  | 85.3 | 77.1 | 95.8 |
  | 82.6 | 84.1 | 97.2 |
  | 80.0 | 91.0 | 98.5 |
  | 77.7 | 97.6 | 99.6 |
  
  Vapor-liquid Equilibrium for o-Xylene/Ethanol P = 101.3 kPa :
  
  | BP Temp. °C | % by mole ethanol | % by mole ethanol |
  | - | - | - |
  | BP Temp. °C | liquid | vapor |
  | 78.3 | 99.52 | 99.66 |
  | 78.7 | 98.59 | 99.03 |
  | 78.7 | 97.73 | 98.52 |
  | 79.0 | 95.78 | 97.40 |
  | 79.3 | 90.59 | 95.09 |
  | 79.7 | 86.79 | 94.16 |
  | 80.0 | 85.01 | 93.70 |
  | 80.2 | 80.91 | 92.91 |
  | 80.3 | 76.77 | 92.36 |
  | 82.0 | 67.69 | 91.21 |
  | 83.8 | 48.66 | 89.25 |
  | 88.1 | 25.11 | 87.32 |
  | 97.3 | 10.94 | 81.49 |
  | 112.8 | 5.22 | 65.91 |
  | 137.3 | 0.65 | 22.90 |
  
  Vapor-liquid Equilibrium for o-Xylene/Methanol P = 101.3 kPa :
  
  | BP Temp. °C | % by mole Methanol | % by mole Methanol |
  | - | - | - |
  | BP Temp. °C | liquid | vapor |
  | 64.7 | 98.78 | 99.10 |
  | 64.8 | 98.33 | 98.81 |
  | 64.8 | 97.67 | 98.45 |
  | 64.9 | 96.70 | 97.96 |
  | 65.3 | 93.34 | 96.82 |
  | 65.7 | 86.84 | 95.68 |
  | 66.3 | 84.24 | 95.31 |
  | 66.7 | 83.30 | 95.65 |
  | 67.3 | 76.74 | 94.97 |
  | 68.4 | 49.33 | 94.52 |
  | 71.5 | 21.76 | 93.84 |
  | 102.1 | 2.49 | 80.00 |
  
  ## 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 | |
  
  * view
  * Except where noted otherwise, data relate to Standard temperature and pressure.
  * Reliability of data general note.
  