This page provides supplementary data to the article properties of water.
Further comprehensive authoritative data can be found at the NIST Chemistry WebBook page on thermophysical properties of fluids.
Structure and properties
Structure and properties Index of refraction, nD 1.333 at 20 °C Dielectric constant88.00 at 0 °C 86.04 at 5 °C 84.11 at 10 °C 82.22 at 15 °C 80.36 at 20 °C 78.54 at 25 °C 76.75 at 30 °C 75.00 at 35 °C 73.28 at 40 °C 71.59 at 45 °C 69.94 at 50 °C 66.74 at 60 °C 63.68 at 70 °C 60.76 at 80 °C 57.98 at 90 °C 55.33 at 100 °C Bond strength 492.215 kJ/mol O–H bond dissociation energy Bond length 95.87 pm (equilibrium) Bond angle 104.48° (equilibrium) Magnetic susceptibility −9.04 × 10−6 volume SI units
Thermodynamic properties
Phase behavior Triple point 273.16 K (0.01 °C), 611.73 Pa Critical point 647 K (374 °C), 22.1 MPa Enthalpy changeof fusion at 273.15 K, ΔfusH 6.01 kJ/mol Entropy change of fusion at 273.15 K, 1 bar, ΔfusS 22.0 J/(mol·K) Std enthalpy changeof vaporization, ΔvapHo 44.0 kJ/mol Enthalpy change of vaporization at 373.15 K, ΔvapH 40.68 kJ/mol Std entropy changeof vaporization, ΔvapSo 118.89 J/(mol·K) Entropy change of vaporization at 373.15 K, ΔvapS 109.02 J/(mol·K) Enthalpy change of sublimation at 273.15 K, ΔsubH 51.1 kJ/mol Std entropy change of sublimation at 273.15 K, 1 bar, ΔsubS ~144 J/(mol·K) Molal freezing point constant −1.858 °C kg/mol Molal boiling point constant 0.512 °C kg/molSolid properties Std enthalpy changeof formation, ΔfHosolid −291.83 kJ/mol Standard molar entropy,Sosolid 41 J/(mol K) Heat capacity, cp 12.2 J/(mol K) at −200 °C 15.0 J/(mol K) at −180 °C 17.3 J/(mol K) at −160 °C 19.8 J/(mol K) at −140 °C 24.8 J/(mol K) at −100 °C 29.6 J/(mol K) at −60 °C 32.77 J/(mol K) at −38.3 °C 33.84 J/(mol K) at −30.6 °C 35.20 J/(mol K) at −20.8 °C 36.66 J/(mol K) at −11.0 °C 37.19 J/(mol K) at −4.9 °C 37.84 J/(mol K) at −2.2 °CLiquid properties Std enthalpy changeof formation, ΔfHoliquid −285.83 kJ/mol Standard molar entropy,Soliquid 69.95 J/(mol K) Heat capacity, cp 75.97 J/(mol K) and 4.2176 J/(g·K) at 0 °C 75.52 J/(mol K) and 4.1921 J/(g·K) at 10 °C 75.33 J/(mol K) and 4.1818 J/(g·K) at 20 °C 75.28 J/(mol K) and 4.1787 J/(g·K) at 25 °C 75.26 J/(mol K) and 4.1784 J/(g·K) at 30 °C 75.26 J/(mol K) and 4.1785 J/(g·K) at 40 °C 75.30 J/(mol K) and 4.1806 J/(g·K) at 50 °C 75.37 J/(mol K) and 4.1843 J/(g·K) at 60 °C 75.46 J/(mol K) and 4.1895 J/(g·K) at 70 °C 75.58 J/(mol K) and 4.1963 J/(g·K) at 80 °C 75.74 J/(mol K) and 4.2050 J/(g·K) at 90 °C 75.94 J/(mol K) and 4.2159 J/(g·K) at 100 °CGas properties Std enthalpy changeof formation, ΔfHogas −241.83 kJ/mol Standard molar entropy,Sogas 188.84 J/(mol K) Heat capacity, cp 36.5 J/(mol K) at 100 °C 36.1 J/(mol K) at 200 °C 36.2 J/(mol K) at 400 °C 37.9 J/(mol K) at 700 °C 41.4 J/(mol K) at 1000 °C Heat capacity, cv 27.5 J/(mol K) at 100 °C 27.6 J/(mol K) at 200 °C 27.8 J/(mol K) at 400 °C 29.5 J/(mol K) at 700 °C 33.1 J/(mol K) at 1000 °C Heat capacity ratio, γ = cp/cv 1.324 at 100 °C 1.310 at 200 °C 1.301 at 400 °C 1.282 at 700 °C 1.252 at 1000 °C van der Waals' constants a = 553.6 L2 kPa/mol2 b = 0.03049 L/mol
Liquid physical properties
Velocity of sound in water c in distilled water at 25 °C 1498 m/s c at other temperatures 1403 m/s at 0 °C1427 m/s at 5 °C1447 m/s at 10 °C1481 m/s at 20 °C1507 m/s at 30 °C1526 m/s at 40 °C1541 m/s at 50 °C1552 m/s at 60 °C1555 m/s at 70 °C1555 m/s at 80 °C1550 m/s at 90 °C1543 m/s at 100 °CDensity0.983854 g/cm3 at −30 °C0.99221 g/cm3 at 40 °C0.993547 g/cm3 at −20 °C0.99022 g/cm3 at 45 °C0.998117 g/cm3 at −10 °C 0.98804 g/cm3 at 50 °C 0.9998395 g/cm3 at 0 °C 0.98570 g/cm3 at 55 °C 0.999972 g/cm3 at 3.984 °C 0.9999720 g/cm3 at 4 °C 0.98321 g/cm3 at 60 °C 0.99996 g/cm3 at 5 °C 0.98056 g/cm3 at 65 °C 0.9997026 g/cm3 at 10 °C 0.97778 g/cm3 at 70 °C 0.9991026 g/cm3 at 15 °C 0.97486 g/cm3 at 75 °C 0.9982071 g/cm3 at 20 °C 0.97180 g/cm3 at 80 °C0.9977735 g/cm3 at 22 °C 0.96862 g/cm3 at 85 °C 0.9970479 g/cm3 at 25 °C 0.96531 g/cm3 at 90 °C 0.9956502 g/cm3 at 30 °C 0.96189 g/cm3 at 95 °C 0.99403 g/cm3 at 35 °C 0.95835 g/cm3 at 100 °C The values below 0 °C refer to supercooled water.Viscosity 1.7921 mPa·s (cP) at 0 °C 0.5494 mPa·s at 50 °C 1.5188 mPa·s at 5 °C 0.5064 mPa·s at 55 °C 1.3077 mPa·s at 10 °C 0.4688 mPa·s at 60 °C 1.1404 mPa·s at 15 °C 0.4355 mPa·s at 65 °C 1.0050 mPa·s at 20 °C 0.4061 mPa·s at 70 °C 0.8937 mPa·s at 25 °C 0.3799 mPa·s at 75 °C 0.8007 mPa·s at 30 °C 0.3635 mPa·s at 80 °C 0.7225 mPa·s at 35 °C 0.3355 mPa·s at 85 °C 0.6560 mPa·s at 40 °C 0.3165 mPa·s at 90 °C 0.5988 mPa·s at 45 °C 0.2994 mPa·s at 95 °C 0.2838 mPa·s at 100 °CSurface tension 75.64 dyn/cm at 0 °C 69.56 dyn/cm at 40 °C 74.92 dyn/cm at 5 °C 68.74 dyn/cm at 45 °C 74.22 dyn/cm at 10 °C 67.91 dyn/cm at 50 °C 73.49 dyn/cm at 15 °C 66.18 dyn/cm at 60 °C 72.75 dyn/cm at 20 °C 64.42 dyn/cm at 70 °C 71.97 dyn/cm at 25 °C 62.61 dyn/cm at 80 °C 71.18 dyn/cm at 30 °C 60.75 dyn/cm at 90 °C 70.38 dyn/cm at 35 °C 58.85 dyn/cm at 100 °C
+ Electrical conductivity of highly purified water at saturation pressureRevised Release on Viscosity and Thermal Conductivity of Heavy Water Substance , The International Association for the Properties of Water and Steam Lucerne, Switzerland, August 2007. Temperature, °C Conductivity, μS/m0.011.15255.5010076.5200299300241
Water/steam equilibrium properties Vapor pressure formula for steam in equilibrium with liquid water:
where P is equilibrium vapor pressure in kPa, and T is temperature in kelvins.
For T = 273 K to 333 K: A = 7.2326; B = 1750.286; C = 38.1.
For T = 333 K to 423 K: A = 7.0917; B = 1668.21; C = 45.1.
Steam tableTemperature(°C)Pressure(kPa)H of liquid(J/g)ΔvapH(J/g)Wvap(J/g)ρ of vapor(kg/m3) 0 0.612 0.00 2496.5 126.0 0.004855 10 1.227 42.0 2473.5 130.5 0.009498 20 2.336 83.8 2450.9 135.1 0.01728 30 4.242 125.6 2427.9 139.7 0.03037 40 7.370 167.2 2404.9 144.2 0.05107 50 12.33 209.0 2381.4 148.7 0.08275 60 19.90 250.8 2357.6 153.0 0.1300 70 31.15 292.7 2332.9 157.3 0.1979 80 46.12 334.6 2307.7 161.5 0.2930 90 70.10 376.6 2282.6 165.5 0.4232 100 101.32 419.0 2256.3 169.4 0.5974 110 143.27 460.8 2229.5 173.1 0.8264 120 198.50 503.2 2201.4 176.7 1.121 130 270.13 545.8 2172.5 180.2 1.497 140 361.4 588.5 2142.8 183.2 1.967 150 476.0 631.5 2111.8 186.1 2.548 160 618.1 674.7 2080.0 188.7 3.263 170 792.0 718.5 2047.0 190.6 4.023 180 1002.7 762.5 2012.2 192.8 5.165 190 1254.9 807.0 1975.8 194.5 6.402 200 1554.3 851.9 1937.3 195.6 7.868 210 1907.9 897.5 1897.5 196.3 9.606 221.1 2369.8 948.5 1850.2 196.6 11.88 229.4 2769.6 987.9 1812.5 196.2 13.87 240.6 3381.1 1040.6 1759.4 195.1 16.96 248.9 3904.1 1080.3 1715.8 193.7 19.66 260.0 4695.9 1134.8 1653.9 190.8 23.84 271.1 5603.4 1195.9 1586.5 186.9 28.83 279.4 6366.5 1240.7 1532.5 183.3 33.18 290.6 7506.2 1302.3 1456.3 177.4 39.95 298.9 8463.9 1350.0 1394.8 172.2 45.93 310.0 9878.0 1415.7 1307.7 164.2 55.25 321.1 11461 1483.9 1212.7 154.5 66.58 329.4 12785 1537.9 1133.2 145.6 76.92 340.6 14727 1617.9 1007.6 130.9 94.25 348.9 16331 1687.0 892.0 117.0 111.5 360.0 18682 1797.0 694.0 91.0 145.3 371.1 21349 1968.3 365.0 47.0 214.5 374.4 22242 2151.2 0 0 306.8Temperature(°C)Pressure(kPa)H of liquid(J/g)ΔvapH(J/g)Wvap(J/g)ρ of vapor(kg/m3)
Data in the table above is given for water–steam equilibria at various temperatures over the entire temperature range at which liquid water can exist. Pressure of the equilibrium is given in the second column in kPa. The third column is the heat content of each gram of the liquid phase relative to water at 0 °C. The fourth column is the heat of vaporization of each gram of liquid that changes to vapor. The fifth column is the work PΔV done by each gram of liquid that changes to vapor. The sixth column is the density of the vapor.
Melting point of ice at various pressures Data obtained from CRC Handbook of Chemistry and Physics 44th ed., p. 2390.
Pressure kPa Temp. °C 101.325 0.0 32950 −2.5 60311 −5.0 87279 −7.5 113267 −10.0 138274 −12.5 159358 −15.0 179952 −17.5 200251 −20.0 215746 −22.1
Table of various forms of ice Properties of various forms of ice Iceform Densityg/cm3 Crystalstructure Triplepoints TP temp °C TP pressureMPaIh0.92hexagonal Lq, Vap, Ih 0.01 0.000612 Lq, Ih, III −22.0 207.5 Ih, II, III −34.7 212.9Ic0.92cubic II1.17rhombohedral Ih, II, III −34.7 212.9 II, III, V −24.3 344.3 II, V, VI −55 (est) 620III1.14tetragonal Lq, Ih, III −22.0 207.5 Lq, III, V −17 346.3 Ih, II, III −34.7 212.9 II, III, V −24.3 344.3IV1.27rhombohedral V1.23monoclinic Lq, III, V −17 346.3 Lq, V, VI 0.16 625.9 II, III, V −24.3 344.3 II, V, VI −55 (est) 620VI1.31tetragonal Lq, V, VI 0.16 625.9 Lq, VI, VII 81.6 2200 II, V, VI −55 (est) 620 VI, VII, VIII ≈5 2100VII1.50cubic Lq, VI, VII 81.6 2200 VI, VII, VIII ≈5 2100 VII, VIII, X −173 62000VIII1.46tetragonal VI, VII, VIII ≈5 2100 VII, VIII, X −173 62000IX1.16tetragonal X2.46cubic VII, VIII, X −173 62000XI‡0.92orthorhombic Vap, Ih, XI −201.5 0 (expected)XII1.29tetragonal XIII1.23monoclinic XIV1.29orthorhombic ‡Ice XI triple point is theoretical and has never been obtained
Phase diagram
Water with dissolved NaCl
+ Properties of water–NaCl mixtures NaCl, wt% Teq, °C ρ, g/cm3 n η, mPa·s0 0 0.99984 1.333 1.0020.5 −0.3 1.0018 1.3339 1.0111 −0.59 1.0053 1.3347 1.022 −1.19 1.0125 1.3365 1.0363 −1.79 1.0196 1.3383 1.0524 −2.41 1.0268 1.34 1.0685 −3.05 1.034 1.3418 1.0856 −3.7 1.0413 1.3435 1.1047 −4.38 1.0486 1.3453 1.1248 −5.08 1.0559 1.347 1.1459 −5.81 1.0633 1.3488 1.16810 −6.56 1.0707 1.3505 1.19312 −8.18 1.0857 1.3541 1.2514 −9.94 1.1008 1.3576 1.31716 −11.89 1.1162 1.3612 1.38818 −14.04 1.1319 1.3648 1.46320 −16.46 1.1478 1.3684 1.55722 −19.18 1.164 1.3721 1.67623.3 −21.1 23.7 −17.3 24.9 −11.1 26.1 −2.7 26.28 0 26.32 10 26.41 20 26.45 25 26.52 30 26.67 40 26.84 50 27.03 60 27.25 70 27.5 80 27.78 90 28.05 100
Note: ρ is density, n is refractive index at 589 nm, and η is viscosity, all at 20 °C; Teq is the equilibrium temperature between two phases: ice/liquid solution for Teq < 0–0.1 °C and NaCl/liquid solution for Teq above 0.1 °C.
Self-ionization
°C −35 0 25 60 300 (~50 MPa)pKw 17 14.9 14.0 13.0 12
Spectral data
UV-Vis λmax ? nm Extinction coefficient, ε ?IR Major absorption bands vapor: ν1 = 3657.05, ν2 = 1594.75, ν3 = 3755.93 cm−1liquid: ν1 = 3280, ν2 = 1644, ν3 = 3490 cm−1 hexagonal ice: ν1 = 3085, ν2 = 1650, ν3 = 3220 cm−1NMR Proton NMR 4.79 ppm in D2O; 1.56 ppm in CDCl3; 0.40 ppm in C6D6; 4.87 in CD3OD Carbon-13 NMR N/A Other NMR data MS Masses of main fragments
Self-diffusion coefficients Experimental self-diffusion coefficients at various temperaturesTemperature in °CCoefficients in m2/s01.09911.13841.26151.303101.525151.765202.023252.299302.594352.907403.238453.588503.956564.423604.748705.615806.557907.5741008.667
Additional data translated from German "Wasser (Stoffdaten)" page
The data that follows was copied and translated from the German language Wikipedia version of this page (which has moved to here). It provides supplementary physical, thermodynamic, and vapor pressure data, some of which is redundant with data in the tables above, and some of which is additional.
Physical and thermodynamic tables In the following tables, values are temperature-dependent and to a lesser degree pressure-dependent, and are arranged by state of aggregation (s = solid, lq = liquid, g = gas), which are clearly a function of temperature and pressure. All of the data were computed from data given in "Formulation of the Thermodynamic Properties of Ordinary Water Substance for Scientific and General Use" (IAPWS, 1984) (obsolete as of 1995). This applies to: T – temperature in degrees Celsius V – specific volume in cubic decimeters per kilogram (1 dm3 is equivalent to 1 liter) H – specific enthalpy in kilojoules per kilogram U – specific internal energy in kilojoules per kilogram S – specific entropy in kilojoules per kilogram-kelvin