Deuterium oxide physical properties

The slightly different physical properties of deuterium allow its concentration in ordinary hydrogen (or the concentration of a deuterium-containing compound in a hydrogen compound) to be determined. Exchange of deuterium and hydrogen occurs and can be used to elucidate the mechanism of reactions (i.e. the deuterium is a non-radioactive tracer). Methanol exchanges with deuterium oxide thus ... 

Let us now look into the basic characteristics of the freezing/melting process of water. Under normal conditions (and probably in the presence of impurities), bulk water fijeezes into a hexagonal lattice with a release of 1.44 kcal/mol of latent heat This is accompanied by an increase of volume, as mentioned earher, of 8%. Water also has a variety where two hydrogen atoms can be replaced by deuterium. This is called deuterium oxide or heavy water (D2O). It has physical properties similar to normal water Avith some modification due to the isotope effect In the case of heavy... 

This treatise is an exhaustive compilation of physical data on heavy water (deuterium oxide). Some of the more relevant properties that are covered include densities, critical constants, vapor pressures, enthalpies of transition, viscosity, and thermal conductivity, equation of state, and tables of thermodynamic properties as functions of temperature and pressure. 

The physical and thermodynamic properties of elemental hydrogen and deuterium and of their respective oxides illustrate the effect of isotopic mass differences. 

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