Water Properties (abbreviated list)

**List of physical data concerning liquid H₂O** ^*
Property	Data
Area, surface covered	19.0 Å² ˣ mol⁻¹ (monolayer [795 ])
Atmospheric content	19.66 g ˣ kg⁻¹ (relative humidity = 100)
Boiling point	100.0 °C, 373.1243 K see [88]
Compressibility, adiabatic (β_S)	0.4477 GPa⁻¹ [620 ]
Compressibility, isothermal (β_T)	0.4599 GPa⁻¹ [507]
Conductivity, electrolytic	0.055 01 μS ˣ cm⁻¹ [737])
Conductivity, thermal	0.610 W ˣ m⁻¹ ˣ K⁻¹[IAPWS]
Critical point	647.096 K, 22.064 MPa, 322 kg ˣ m⁻³ (IAPWS)
Cryoscopic constant	1.8597 K ˣ kg ˣ mol⁻¹
Density	997.05 kg ˣ m⁻³ [67, 112]
Dielectric constant	78.4 [63]
Diffusion coefficient	0.2299 Å² ˣ ps⁻¹[1933]
Dipole moment, μ	2.95±0.2 D (liquid, 27 °C) [129]
Ebullioscopic constant	0.5129 K ˣ kg ˣ mol⁻¹
Enthalpy of vaporization	40.657 kJ ˣ mol⁻¹ (100 °C) [61]
Enthalpy of fusion	6.00678 kJ ˣ mol⁻¹ (0 °C) [1385 ]
Expansion coefficient (α)	0.000253 °C⁻¹ [68]
Magnetic susceptibility	-1.64 ˣ 10⁻¹⁰ m³ ˣ mol⁻¹ [670 ]
Melting point	0.00 °C, 273.152 519 K (IAPWS)
Molality	55.508 472 mol ˣ kg ⁻¹
Molar concentration	55.345 mol ˣ L⁻¹
Molar mass	18.015 268 g ˣ mol⁻¹
pH	6.9996 (based on [112])
pK_a	13.995 (25 °C) [2965]
pK_w	13.9991 [112]
Refractive index	1.332 86 (λ = 589.26 nm) [310]
Resistance, electrical	18.18 MΩ cm [737 ]
Specific heat capacity, C_P	75.338 J ˣ mol⁻¹ ˣ K⁻¹ calculated from [1154 ]
Specific heat capacity, C_v	74.539 J ˣ mol⁻¹ ˣ K⁻¹ [67]
Speed of sound	1496.7 m ˣ s⁻¹ [620]
Surface tension	0.07198 J ˣ m⁻² [IAPWS]
Triple point	0.01 °C, 611.657 Pa, 0.99978 g ˣ cm⁻³ [536]
Vapor pressure	3.165 kPa [808]
Viscosity, dynamic	0.8909 mPa s [IAPWS]
Viscosity, kinematic	0.8935 ˣ 10⁻⁶ m² ˣ s⁻¹
Volume, molar	18.0685 cm³ [1006 ]

^* All the data is for liquid water at 25 °C, 101.325 kPa, unless other conditions clearly apply. For more details, go to the extended list.