This page provides supplementary chemical data on dimethyl sulfoxide.
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,Merck Index of Chemicals and Drugs, 9th ed. monograph 3249 nD 1.4795 at 20 °C1.4787 at 21 °C Abbe number? Dielectric constant, εr 48 ε0 at 20 °C Bond strength ? Bond length ? Bond angle ? Magnetic susceptibility ? Surface tension 43 dyn/cm at 20 °C Viscosity 2.14 mPa·s at 20 °C1.1 mPa·s at 27 °C
Thermodynamic properties
Phase behavior Triple point 291.67 K (18.52 °C), ? Pa Critical point 720 K (447 °C), 5630 kPa Std enthalpy changeof fusion, ΔfusHo 14.37 kJ/mol Std entropy changeof fusion, ΔfusSo 49.26 J/(mol·K) Std enthalpy changeof vaporization, ΔvapHo 52.9 kJ/mol Std entropy changeof vaporization, ΔvapSo ? J/(mol·K) Solid properties Std enthalpy changeof formation, ΔfHosolid ? kJ/mol Standard molar entropy,Sosolid ? J/(mol K) Heat capacity, cp 149.40 J/(mol·K) Liquid properties Std enthalpy changeof formation, ΔfHoliquid −203.4 kJ/mol Standard molar entropy,Soliquid 188.78 J/(mol·K) Enthalpy of combustion, ΔcHo −2037.3 kJ/mol Heat capacity, cp 153 J/(mol·K) at 25 °C Gas properties Std enthalpy changeof formation, ΔfHogas −150.5 kJ/mol Standard molar entropy,Sogas ? J/(mol·K) Heat capacity, cp ? J/(mol·K)
Vapor pressure of liquid vapor pressure at 20 °C = 0.556 mbar = 0.417 mmHg
Distillation data Vapor-liquid equilibriumfor dimethyl sulfoxide/waterP = 550 mm Hg BPTemp.°C % by mole water liquid vapor 168.4 6.5 34.6 160.9 10.8 51.8 153.1 16.4 62.7 146.4 21.2 71.0 140.6 26.7 78.4 135.1 32.1 83.9 130.8 37.4 87.6 124.3 44.8 91.7 121.0 48.5 93.5 114.9 55.4 96.0 107.8 66.4 98.0 102.1 74.4 98.9 97.2 84.0 99.6 96.3 85.7 99.6 93.9 91.9 99.8 Vapor-liquid equilibriumfor dimethyl sulfoxide/ethanolP = 14.665 kPa BPTemp.°C % by mole DMSO liquid vapor 55.80 48.75 1.0 64.50 59.75 1.6 66.75 64.00 2.5 70.80 71.00 3.6 76.50 76.25 5.0 81.50 80.50 6.0 91.50 85.00 13.0 100.74 90.00 21.0
Spectral data
UV-Vis λmax <220 nm Extinction coefficient, ε 0.0034 %−1 cm−1 in unpHed water at 260 nm IR Spectrum NIST Major absorption bands 3000, 2900, 1200–1240, 1000–1080, 960, 690 cm−1 NMR Proton NMR 2.54((CD3)2SO), 2.71 in D2O; Carbon-13 NMR 40ppm; Other NMR data MS Masses of main fragments
References