This page provides supplementary data to the article properties of water.
Contents
- Watersteam equilibrium properties
- Melting point of ice at various pressures
- Table of various forms of ice
- Water with dissolved NaCl
- Additional data translated from German Wasser Stoffdaten page
- Physical and thermodynamic tables
- Standard conditions
- Triple point
- Saturated vapor pressure
- Formulas
- Magnetic Susceptibility
- Disclaimer
- References
Further comprehensive authoritative data can be found at the NIST Webbook page on thermophysical properties of fluids.
Water/steam equilibrium properties
Vapor pressure formula for steam in equilibrium with liquid water:
log10(P) = A − B / (T − C),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.
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 PV work 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
Table of various forms of ice
‡Ice XI triple point is theoretical and has never been obtained
Water with dissolved NaCl
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 and NaCl/liquid solution for Teq above 0.1 °C.
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" (1984). This applies to:
Standard conditions
In the following table, material data are given for standard pressure of 0.1 MPa (equivalent to 1 bar). Up to 99.63 °C (the boiling point of water at 0.1 MPa), at this pressure water exists as a liquid. Above that, it exists as water vapor. Note that the boiling point of 100.0 °C is at a pressure of 0.101325 MPa (1 atm), which is the average atmospheric pressure.
Triple point
In the following table, material data are given with a pressure of 611.7 Pa (equivalent to 0.006117 bar). Up to a temperature of 0.01 °C, the triple point of water, water normally exists as ice, except for supercooled water, for which one data point is tabulated here. At the triple point, ice can exist together with both liquid water and vapor. At higher temperatures, the data are for water vapor only.
Saturated vapor pressure
The following table is based on different, complementary sources and approximation formulas, whose values are of various quality and accuracy. The values in the temperature range of −100 °C to 100 °C were inferred from D. Sunday (1982) and are quite uniform and exact. The values in the temperature range of the boiling point of water up to the critical point (100 °C to 374 °C) are drawn from different sources and are substantially less accurate; hence they should be used only as approximate values.
To use the values correctly, consider the following points:
Formulas
The table values for −100 °C to 100 °C were computed by the following formulas, where T is in kelvins and vapor pressures, Pw and Pi, are in pascals.
Over liquid water
loge(Pw) = −6094.4642 T−1 + 21.1249952 − 2.724552×10−2 T + 1.6853396×10−5 T2 + 2.4575506 loge(T)For temperature range: 173.15 K to 373.15 K or equivalently −100 °C to 100 °C
Over ice
loge(Pi) = −5504.4088 T−1 − 3.5704628 − 1.7337458×10−2 T + 6.5204209×10−6 T2 + 6.1295027 loge(T)For temperature range: 173.15 K to 273.15 K or equivalently −100 °C to 0 °C
At triple point
An important basic value, which is not registered in the table, is the saturated vapor pressure at the triple point of water. The internationally accepted value according to measurements of Guildner, Johnson and Jones (1976) amounts to:
Pw(ttp = 0.01 °C) = 611.657 Pa ± 0.010 Pa at (1 − α) = 99%Magnetic Susceptibility
Accepted standardized value of the magnetic susceptibility of water at 20oC (room temperature) is -12.97 cm3/mol.
Accepted standardized value of the magnetic susceptibility of water at 20oC (room temperature) is -0.702 cm3/g.
Disclaimer
Except where noted otherwise, data relate to standard ambient temperature and pressure.
Disclaimer applies.