Heavy Water - Thermophysical Properties

Heavy water ( deuterium oxide , ²H₂O , D₂O ) is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium (= heavy hydrogen = ²H = D), rather than the common hydrogen-1 isotope (¹H = H = protium) that makes up most of the hydrogen in normal water.

Thermodynamic properties of heavy water - D₂O:

• Boiling temperature (at 101.325 kPa):     101.40 ^oC = 214.52 °F
• Bulk modulus elasticity (at 25°C):              2.10×10⁹ Pa or N/m²
• Critical density:                                         0.356 g/cm³ = 0.691 slug/ft³ = 3.457 lb_m/gal(US)
• Critical pressure :                                      213.88 atm = 220.98 bar = 21.671 MPa (MN/m²) = 3143 psi (=lb_f/in²)
• Critical temperature :                                 370.697 ^oC = 699.255 °F
• Ionization constant, pK_w (at 25°C):          14.951
• Latent heat of evaporation (at 101.4°C):  41.521 KJ/mol = 2073.20 kJ/kg = 891.32 Btu(IT)/lb
• Latent heat of fusion:                               6.132 kJ/mol = 306.2 kJ/kg = 131.64 Btu(IT)/lb
• Maximum density (at 11.23 ^oC):               1105.9 kg/m³ = 2.1460 slug/ft³ = 10.74048 lb_m/gal(US)
• Melting temperature (at 101.325 kPa):     3.81 ^oC = 38.86 °F
• Molar mass:                                              20.02751 g/mol
• pD (~pH) (at 25°C):                                  7.43
• Specific heat (C_p) water (at 20°C):           4.219 kJ/kgK = 1.008 Btu(IT)/(lb_m °F) or kcal/(kg K)
• Specific weight (at 11.23 ^oC):                   10.8452 kN/m³ = 69.0391 lb_f/ft³
• Surface tension (at 25°C):                       71.87 dyn/cm
• Triple point pressure:                               0.00652 atm = 0.00661 bar = 661 Pa = 0.0959 psi (=lb_f/in²)
• Triple point temperature:                          3.82 °C = 38.88 °F
• Vapor pressure (at 25°C):                        20.6 mmHg = 0.027 atm = 0.028 bar = 2750 Pa = 0.398 psi
• Viscosity (at 20°C):                                   1.251 cP or mPa s

Ionization Constant, pK_w , of normal and heavy water with varying temperature.

See also more about atmospheric pressure, and STP - Standard Temperature and Pressure & NTP - Normal Temperature and Pressure,
as well as Thermophysical properties of: Acetone, Acetylene, Air, Ammonia, Argon, Benzene, Butane, Carbon dioxide, Carbon monoxide, Ethane, Ethanol, Ethylene, Helium, Hydrogen, Hydrogen sulfide, Methane, Methanol, Nitrogen, Oxygen, Pentane, Propane, Toluene and Water.