Chemical Properties of Cyclohexane, butyl- (CAS 1678-93-9)

Cyclohexane, butyl-

InChI
InChI=1S/C10H20/c1-2-3-7-10-8-5-4-6-9-10/h10H,2-9H2,1H3
InChI Key
GGBJHURWWWLEQH-UHFFFAOYSA-N
Formula
C10H20
SMILES
CCCCC1CCCCC1
Molecular Weight1
140.27
CAS
1678-93-9
Other Names
  • 1-CYCLOHEXYLBUTANE
  • Butane, 1-cyclohexyl-
  • Butylcyclohexane
  • Cyclohexane, n-butyl-
  • n-Butylcyclohexane
Cheméo is a service of Céondo GmbH, since 2007, we provide simulation, modelling and software development services for the industry. Do not hesitate to contact us for your projects.

Physical Properties

Property Value Unit Source
ω 0.3620 KDB
Δcliquid -6530.30 ± 1.20 kJ/mol NIST
Δf 56.48 kJ/mol KDB
Δfgas [-213.30; -213.20] kJ/mol Show Hide
Δfgas -213.30 kJ/mol KDB
Δfgas -213.20 ± 1.40 kJ/mol NIST
Δfliquid -263.20 ± 1.30 kJ/mol NIST
Δfus 13.49 kJ/mol Joback Calculated Property
Δvap [47.00; 50.03] kJ/mol Show Hide
Δvap 49.37 kJ/mol NIST
Δvap Outlier 47.00 ± 0.20 kJ/mol NIST
Δvap 48.90 ± 0.50 kJ/mol NIST
Δvap 49.40 ± 0.30 kJ/mol NIST
Δvap 49.40 ± 0.40 kJ/mol NIST
Δvap 49.40 kJ/mol NIST
Δvap 50.00 kJ/mol NIST
Δvap 50.03 kJ/mol NIST
Δvap 50.00 kJ/mol NIST
Δvap 50.00 kJ/mol NIST
IE [9.41; 9.57] eV Show Hide
IE 9.41 eV NIST
IE 9.57 ± 0.03 eV NIST
log10WS -5.42 Relay (1.0) Calculated Property
logPoct/wat 3.757 Crippen Calculated Property
McVol 140.900 ml/mol McGowan Calculated Property
Pc [2560.00; 3150.00] kPa Show Hide
Pc 3150.00 kPa KDB
Pc 2560.00 kPa Critical Point Measurements for Five n-Alkylcyclohexanes (C6 to C10) by the Pulse-Heating Method
Inp [1022.00; 1061.00]   Show Hide
Inp 1047.00 NIST
Inp 1024.00 NIST
Inp 1051.30 NIST
Inp Outlier 1060.90 NIST
Inp 1024.00 NIST
Inp 1025.00 NIST
Inp 1036.00 NIST
Inp 1036.00 NIST
Inp 1045.00 NIST
Inp 1030.00 NIST
Inp 1037.00 NIST
Inp Outlier 1061.00 NIST
Inp 1029.00 NIST
Inp Outlier 1061.00 NIST
Inp 1025.00 NIST
Inp 1032.00 NIST
Inp 1035.00 NIST
Inp 1026.00 NIST
Inp 1052.00 NIST
Inp 1033.80 NIST
Inp 1030.20 NIST
Inp 1028.90 NIST
Inp 1026.60 NIST
Inp 1030.20 NIST
Inp 1031.60 NIST
Inp 1026.60 NIST
Inp 1030.20 NIST
Inp 1031.60 NIST
Inp 1030.20 NIST
Inp 1028.90 NIST
Inp 1028.46 NIST
Inp 1023.13 NIST
Inp 1026.83 NIST
Inp 1029.30 NIST
Inp 1028.77 NIST
Inp 1032.57 NIST
Inp 1035.27 NIST
Inp 1026.00 NIST
Inp 1027.00 NIST
Inp 1033.10 NIST
Inp 1029.00 NIST
Inp 1041.00 NIST
Inp 1028.00 NIST
Inp 1022.00 NIST
Inp 1025.00 NIST
Inp 1030.00 NIST
Inp 1028.00 NIST
Inp 1048.00 NIST
Inp 1033.80 NIST
Inp 1031.60 NIST
Inp 1028.90 NIST
Inp 1028.77 NIST
I [1075.00; 1123.30]   Show Hide
I 1116.00 NIST
I 1094.00 NIST
I 1100.00 NIST
I 1105.00 NIST
I 1101.70 NIST
I 1107.60 NIST
I 1113.20 NIST
I 1118.10 NIST
I 1123.30 NIST
I 1091.20 NIST
I 1096.70 NIST
I 1116.00 NIST
I 1075.00 NIST
I 1082.00 NIST
I 1082.00 NIST
I 1075.00 NIST
gas 459.78 J/mol×K NIST
liquid 344.97 J/mol×K NIST
Tboil 454.10 K KDB
Tc [653.10; 667.00] K Show Hide
Tc 667.00 K KDB
Tc 653.10 K Gas-Liquid Critical Temperatures of Some Alkenes, Amines, and Cyclic Hydrocarbons
Tfus [196.85; 198.40] K Show Hide
Tfus 198.40 K KDB
Tfus 198.30 ± 0.50 K NIST
Tfus 198.30 ± 0.20 K NIST
Tfus 198.30 ± 0.20 K NIST
Tfus 196.85 ± 0.50 K NIST
Ttriple 198.42 ± 0.02 K NIST
Vc 0.508 m3/kmol Relay (1.0) Calculated Property

Temperature Dependent Properties

Property Value Unit Temperature (K) Source
Cp,gas [299.95; 403.35] J/mol×K [447.75; 644.56] Show Hide
Cp,gas 299.95 J/mol×K 447.75 Joback Calculated Property
Cp,gas 319.42 J/mol×K 480.55 Joback Calculated Property
Cp,gas 337.97 J/mol×K 513.35 Joback Calculated Property
Cp,gas 355.61 J/mol×K 546.16 Joback Calculated Property
Cp,gas 372.37 J/mol×K 578.96 Joback Calculated Property
Cp,gas 388.28 J/mol×K 611.76 Joback Calculated Property
Cp,gas 403.35 J/mol×K 644.56 Joback Calculated Property
Cp,liquid 271.04 J/mol×K 298.15 NIST
η [0.0002640; 0.0086122] Pa×s [209.84; 447.75] Show Hide
η 0.0086122 Pa×s 209.84 Joback Calculated Property
η 0.0030367 Pa×s 249.49 Joback Calculated Property
η 0.0014252 Pa×s 289.14 Joback Calculated Property
η 0.0008027 Pa×s 328.79 Joback Calculated Property
η 0.0005116 Pa×s 368.45 Joback Calculated Property
η 0.0003559 Pa×s 408.10 Joback Calculated Property
η 0.0002640 Pa×s 447.75 Joback Calculated Property
ΔfusH [14.14; 14.20] kJ/mol [198.00; 198.42] Show Hide
ΔfusH 14.20 kJ/mol 198.00 NIST
ΔfusH 14.14 kJ/mol 198.40 NIST
ΔfusH 14.14 kJ/mol 198.40 NIST
ΔfusH 14.16 kJ/mol 198.42 NIST
ΔvapH [38.49; 47.40] kJ/mol [293.50; 454.10] Show Hide
ΔvapH 47.40 ± 0.20 kJ/mol 293.50 NIST
ΔvapH 44.90 kJ/mol 412.00 NIST
ΔvapH 38.49 kJ/mol 454.10 KDB
n0 1.43990 293.15 Density, Viscosity, Refractive Index, and Freezing Point for Binary Mixtures of 1,1'-Bicyclohexyl with Alkylcyclohexane
ρl [746.38; 829.90] kg/m3 [253.15; 363.15] Show Hide
ρl 829.90 kg/m3 253.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 803.07 kg/m3 288.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 799.00 kg/m3 293.00 KDB
ρl 799.33 kg/m3 293.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 799.47 kg/m3 293.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 799.33 kg/m3 293.15 Density, Viscosity, Speed of Sound, Bulk Modulus, Surface Tension, and Flash Point of Selected Ternary Mixtures of n-Butylcyclohexane + a Linear Alkane (n-Hexadcane or n-Dodecane) + an Aromatic Compound (Toluene, n-Butylbenzene, or n-Hexylbenzene)
ρl 799.47 kg/m3 293.15 Excess Molar Volume along with Viscosity and Refractive Index for Binary Systems of Tricyclo[5.2.1.0(2.6)]decane with Five Cycloalkanes
ρl 799.34 kg/m3 293.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 799.37 kg/m3 293.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 799.44 kg/m3 293.15 Excess Molar Volumes and Viscosities of Binary Systems of Butylcyclohexane with n-Alkanes (C7 to C14) at T = 293.15 K to 313.15 K
ρl 795.63 kg/m3 298.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 795.57 kg/m3 298.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 795.71 kg/m3 298.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 795.59 kg/m3 298.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 795.71 kg/m3 298.15 Excess Molar Volume along with Viscosity and Refractive Index for Binary Systems of Tricyclo[5.2.1.0(2.6)]decane with Five Cycloalkanes
ρl 795.70 kg/m3 298.15 Excess Molar Volumes and Viscosities of Binary Systems of Butylcyclohexane with n-Alkanes (C7 to C14) at T = 293.15 K to 313.15 K
ρl 791.84 kg/m3 303.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 791.96 kg/m3 303.15 Excess Molar Volume along with Viscosity and Refractive Index for Binary Systems of Tricyclo[5.2.1.0(2.6)]decane with Five Cycloalkanes
ρl 791.95 kg/m3 303.15 Excess Molar Volumes and Viscosities of Binary Systems of Butylcyclohexane with n-Alkanes (C7 to C14) at T = 293.15 K to 313.15 K
ρl 791.82 kg/m3 303.15 Density, Viscosity, Speed of Sound, Bulk Modulus, Surface Tension, and Flash Point of Selected Ternary Mixtures of n-Butylcyclohexane + a Linear Alkane (n-Hexadcane or n-Dodecane) + an Aromatic Compound (Toluene, n-Butylbenzene, or n-Hexylbenzene)
ρl 791.81 kg/m3 303.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 791.96 kg/m3 303.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 791.88 kg/m3 303.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 788.20 kg/m3 308.15 Excess Molar Volume along with Viscosity and Refractive Index for Binary Systems of Tricyclo[5.2.1.0(2.6)]decane with Five Cycloalkanes
ρl 788.07 kg/m3 308.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 788.19 kg/m3 308.15 Excess Molar Volumes and Viscosities of Binary Systems of Butylcyclohexane with n-Alkanes (C7 to C14) at T = 293.15 K to 313.15 K
ρl 788.12 kg/m3 308.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 784.43 kg/m3 313.15 Excess Molar Volume along with Viscosity and Refractive Index for Binary Systems of Tricyclo[5.2.1.0(2.6)]decane with Five Cycloalkanes
ρl 784.43 kg/m3 313.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 784.35 kg/m3 313.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 784.28 kg/m3 313.15 Density, Viscosity, Speed of Sound, Bulk Modulus, Surface Tension, and Flash Point of Selected Ternary Mixtures of n-Butylcyclohexane + a Linear Alkane (n-Hexadcane or n-Dodecane) + an Aromatic Compound (Toluene, n-Butylbenzene, or n-Hexylbenzene)
ρl 784.27 kg/m3 313.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 784.41 kg/m3 313.15 Excess Molar Volumes and Viscosities of Binary Systems of Butylcyclohexane with n-Alkanes (C7 to C14) at T = 293.15 K to 313.15 K
ρl 784.30 kg/m3 313.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 780.65 kg/m3 318.15 Excess Molar Volume along with Viscosity and Refractive Index for Binary Systems of Tricyclo[5.2.1.0(2.6)]decane with Five Cycloalkanes
ρl 780.49 kg/m3 318.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 780.52 kg/m3 318.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 776.70 kg/m3 323.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 776.74 kg/m3 323.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 777.16 kg/m3 323.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 776.71 kg/m3 323.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 776.70 kg/m3 323.15 Density, Viscosity, Speed of Sound, Bulk Modulus, Surface Tension, and Flash Point of Selected Ternary Mixtures of n-Butylcyclohexane + a Linear Alkane (n-Hexadcane or n-Dodecane) + an Aromatic Compound (Toluene, n-Butylbenzene, or n-Hexylbenzene)
ρl 772.93 kg/m3 328.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 769.09 kg/m3 333.15 Density, Viscosity, Speed of Sound, Bulk Modulus, Surface Tension, and Flash Point of Selected Ternary Mixtures of n-Butylcyclohexane + a Linear Alkane (n-Hexadcane or n-Dodecane) + an Aromatic Compound (Toluene, n-Butylbenzene, or n-Hexylbenzene)
ρl 769.13 kg/m3 333.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 769.55 kg/m3 333.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 769.09 kg/m3 333.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 769.10 kg/m3 333.15 Densities, Viscosities, Speeds of Sound, Bulk Moduli, Surface Tensions, and Flash Points of Quaternary Mixtures of n-Dodecane (1), n-Butylcyclohexane (2), n-Butylbenzene (3), and 2,2,4,4,6,8,8-Heptamethylnonane (4) at 0.1 MPa as Potential Surrogate Mixtures for Military Jet Fuel, JP-5
ρl 765.30 kg/m3 338.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 761.47 kg/m3 343.15 Densities and Viscosities for the Ternary System of Cyclopropanemethanol (1) + n-Dodecane (2) + Butylcyclohexane (3) and Corresponding Binaries at T = 293.15 343.15 K
ρl 761.40 kg/m3 343.15 Density, Viscosity, Speed of Sound, Bulk Modulus, Surface Tension, and Flash Point of Selected Ternary Mixtures of n-Butylcyclohexane + a Linear Alkane (n-Hexadcane or n-Dodecane) + an Aromatic Compound (Toluene, n-Butylbenzene, or n-Hexylbenzene)
ρl 761.43 kg/m3 343.15 Densities, Viscosities, Refractive Indices, and Surface Tensions of Binary Mixtures of 2,2,4-Trimethylpentane with Several Alkylated Cyclohexanes from (293.15 to 343.15) K
ρl 761.88 kg/m3 343.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 754.16 kg/m3 353.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ρl 746.38 kg/m3 363.15 Density, Viscosity, Surface Tension, and Refractive Index for Binary Mixtures of 1,3-Dimethyladamantane with Four C10 Alkanes
ΔfusS 71.36 J/mol×K 198.42 NIST
γ 0.03 N/m 293.20 KDB

Correlations

Property Value Unit Temperature (K) Source
Pvap [1.33; 202.65] kPa [328.36; 484.61] The Yaws Handbook of Vapor Pressure Show Hide
Equationln(Pvp) = A + B/(T + C)
Coefficient A1.39050e+01
Coefficient B-3.63952e+03
Coefficient C-6.10930e+01
Temperature range, min.328.36
Temperature range, max.484.61
Pvap 1.33 kPa 328.36 Calculated Property
Pvap 3.06 kPa 345.72 Calculated Property
Pvap 6.38 kPa 363.08 Calculated Property
Pvap 12.29 kPa 380.44 Calculated Property
Pvap 22.11 kPa 397.80 Calculated Property
Pvap 37.56 kPa 415.17 Calculated Property
Pvap 60.73 kPa 432.53 Calculated Property
Pvap 94.07 kPa 449.89 Calculated Property
Pvap 140.35 kPa 467.25 Calculated Property
Pvap 202.65 kPa 484.61 Calculated Property
Pvap [3.66e-06; 2575.39] kPa [198.42; 667.00] KDB Vapor Pressure Data Show Hide
Equationln(Pvp) = A + B/T + C*ln(T) + D*T^2
Coefficient A7.54321e+01
Coefficient B-8.39938e+03
Coefficient C-8.64335e+00
Coefficient D2.74293e-06
Temperature range, min.198.42
Temperature range, max.667.00
Pvap 3.66e-06 kPa 198.42 Calculated Property
Pvap 3.45e-03 kPa 250.48 Calculated Property
Pvap 0.23 kPa 302.55 Calculated Property
Pvap 3.84 kPa 354.61 Calculated Property
Pvap 27.19 kPa 406.68 Calculated Property
Pvap 113.19 kPa 458.74 Calculated Property
Pvap 331.82 kPa 510.81 Calculated Property
Pvap 765.09 kPa 562.87 Calculated Property
Pvap 1490.65 kPa 614.94 Calculated Property
Pvap 2575.39 kPa 667.00 Calculated Property

Similar Compounds

Cyclohexane, propyl-. Cyclohexane, pentyl-. Cyclohexane, hexadecyl-. Cyclohexane, octadecyl-. Cyclohexane, decyl-. Dodecylcyclohexane. Cyclohexane, octyl-. n-Tridecylcyclohexane. n-Heptadecylcyclohexane. n-Pentadecylcyclohexane. Cyclohexane, tetradecyl-. Cyclohexane, eicosyl-. Cyclohexane, nonadecyl-. Cyclohexane, hexyl-. Heptylcyclohexane.

Find more compounds similar to Cyclohexane, butyl-.

Mixtures

Find more mixtures with Cyclohexane, butyl-.

Sources

Note: Cheméo is only indexing the data, follow the source links to retrieve the latest data. The source is also providing more information like the publication year, authors and more. Take the time to validate and double check the source of the data.
Outlier This icon means that the value is more than 2 standard deviations away from the property mean.