This page provides supplementary chemical data on cyclohexane.
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 and follow its directions. Sigma Aldrich SIRI Science Stuff Fisher Scientific
Structure and properties
Structure and properties Index of refraction, nD 1.4262 at 20 °C Abbe number? Dielectric constant, εr 2.023 ε0 at 20 °C Bond strength ? Bond lengthMorrison, Robert Thornton; Boyd, Robert Neilson: Organic Chemistry 2nd ed. p. 288 230 pm H–C Bond angle 109.5° H–C–H109.5 °C–C–C 109.5° H–C–C Magnetic susceptibility ? Surface tension 27 dyn/cm at 10 °C25.3 dyn/cm at 20 °C15.7 dyn/cm at 80 °C ViscosityLange's Handbook of Chemistry, 10th ed. pp. 1669–1674 1.03 mPa·s at 17 °C0.93 mPa·s at 22 °C0.86 mPa·s at 27 °C0.75 mPa·s at 35 °C
Thermodynamic properties
Phase behavior Triple point 279.48 K (6.33 °C), 5.388 kPaFink H.L.: The Heat Capacity and Entropy. Heats of Transition, Fusion and Vaporization and the Vapor Pressures of Cyclohexane. The Vibrational Frequencies of Alicyclic Ring Systems. J.Am.Chem.Soc. 65 (1943) 1135-1139 Critical point 554 K (281 °C), 4070 kPa Std enthalpy changeof fusion, ΔfusHo 2.68 kJ/molcrystal I → liquid Std entropy changeof fusion, ΔfusSo 9.57 J/(mol·K)crystal I → liquid Std enthalpy changeof vaporization, ΔvapHo 32 kJ/mol Std entropy changeof vaporization, ΔvapSo 111.80 J/(mol·K) Solid properties Std enthalpy changeof formation, ΔfHosolid ? kJ/mol Standard molar entropy,Sosolid ? J/(mol K) Heat capacity, cp ? J/(mol K) Enthalpy of transition, ΔtrsHo 6.7 kJ/mol at –87.0 °Ccrystal II → crystal I Entropy of transition, ΔtrsSo 36 J/(mol·K) at –87.0 °Ccrystal II → crystal I Liquid properties Std enthalpy changeof formation, ΔfHoliquid –156.4 kJ/mol Standard molar entropy,Soliquid 204 J/(mol K) Enthalpy of combustion, ΔcHo –3919.6 kJ/mol Heat capacity, cp 156 J/(mol K) or 1.85 J/(g K) Gas properties Std enthalpy changeof formation, ΔfHogas –123.1 kJ/mol Standard molar entropy,Sogas 298.19 J/(mol K) Heat capacity, cp 105.3 J/(mol K) van der Waals' constantsLange's Handbook of Chemistry 10th ed, pp. 1522–1524 a = 2311 L2 kPa/mol2 b = 0.1424 liter per mole
Vapor pressure of liquid P in mm Hg 1 10 40 100 400 760 1520 3800 7600 15200 30400 45600 T in °C –45.3(s) –15.9(s) 6.7 25.5 60.8 80.7 106.0 146.4 184.0 228.4 — — Table data obtained from CRC Handbook of Chemistry and Physics 44th ed. The "(s)" annotation indicates equilibrium temperature of vapor over solid. Otherwise value is equilibrium temperature of vapor over liquid.
Distillation data Vapor-liquid Equilibriumfor Cyclohexane/BenzeneP = 760 mm Hg BPTemp.°C % by mole benzene liquid vapor 79.5 10.1 13.1 78.9 17.1 21.1 78.4 25.6 29.3 77.8 34.3 37.6 77.5 42.8 44.5 77.4 52.5 52.9 77.4 57.1 56.4 77.6 66.5 64.5 77.9 75.9 72.8 78.2 81.0 77.7 78.6 86.3 83.4 79.3 94.5 92.6 Vapor-liquid Equilibriumfor Cyclohexane/n-HexaneP = 101.0 kPa BPTemp.°C % by mole n-hexane liquid vapor 80.60 0.00 0.00 78.87 7.9 12.12 78.15 12.50 18.30 77.36 18.06 25.19 76.85 21.65 29.30 76.29 25.92 34.13 75.85 29.39 37.92 75.29 33.52 42.38 75.29 37.86 46.93 74.23 41.63 50.71 73.58 46.72 55.63 73.11 50.66 59.21 72.26 59.26 67.28 71.11 69.43 76.07 70.45 76.18 81.40 69.05 90.70 93.13 68.64 100.00 100.00 Vapor-liquid Equilibriumfor Cyclohexane/Acetic acidP = 101.325 kPa BPTemp.°C % by mole acetic acid liquid vapor 79.60 2.75 6.31 79.32 5.20 9.85 78.84 101.2 15.01 78.53 14.06 18.04 78.50 21.39 21.98 78.81 35.30 26.20 79.13 49.30 29.00 79.33 56.10 30.00 81.44 74.60 33.50 81.66 75.80 34.20 85.18 86.70 40.00 90.52 92.50 49.20 91.90 93.20 51.70 95.52 94.57 57.82 98.94 95.96 63.33 105.75 97.84 75.69 113.16 99.33 90.67 Vapor-liquid Equilibriumfor Cyclohexane/EthanolP = 760 mm Hg BPTemp.°C % by mole ethanol liquid vapor 73.99 2.0 17.5 69.08 3.0 30.2 66.94 6.5 35.8 66.08 8.1 36.3 66.37 8.6 36.5 65.59 12.5 38.8 65.23 15.1 39.6 65.12 20.6 40.8 64.93 25.8 41.5 64.87 28.3 41.8 64.84 31.5 42.6 64.78 36.6 43.0 64.77 40.3 43.1 64.77 43.1 43.1 64.78 44.4 43.8 64.81 50.0 44.3 64.88 55.7 45.5 65.01 61.3 46.0 64.99 62.1 45.8 65.25 67.8 47.5 65.56 73.8 50.5 66.03 76.3 49.6 65.93 77.6 51.5 66.40 78.1 49.8 66.90 80.9 54.5 67.26 83.3 57.8 67.98 85.3 59.5 68.86 88.1 62.3 69.44 89.8 65.3 70.11 90.9 67.8 71.42 92.9 72.5 72.48 95.1 77.8 Vapor-liquid Equilibriumfor Cyclohexane/IsopropanolP = 760 mm Hg BPTemp.°C % by mole cyclohexane liquid vapor 78.71 2.7 11.2 76.91 7.0 21.8 74.96 11.6 28.3 74.80 12.0 27.6 72.28 19.1 37.1 70.19 30.6 48.9 69.35 47.3 55.5 69.20 51.6 57.0 69.14 51.6 57.2 69.11 51.8 56.8 68.80 52.8 58.3 69.01 53.8 58.2 69.08 57.1 58.2 69.10 70.8 62.7 69.42 74.2 64.9 69.45 78.4 66.0 69.66 80.7 67.3 70.11 86.2 69.7 70.31 87.3 70.9 71.50 92.1 77.3 74.74 97.8 85.0 76.73 99.5 89.3
Spectral data
UV-Vis λmax ? nm Extinction coefficient, ε ? IR Major absorption bands 1055–1000 cm−1 NMR Proton NMR Carbon-13 NMR Other NMR data MS Masses of main fragments
References