Sublimation and Fusion

The quantities defined by Eqs. (2)—(7) plus Vs max, Vs min, and the positive and negative areas, A and, enable detailed characterization of the electrostatic potential on a molecular surface. Over the past ten years, we have shown that subsets of these quantities can be used to represent analytically a variety of liquid-, solid-, and solution-phase properties that depend on noncovalent interactions [14-17, 84] these include boiling points and critical constants, heats of vaporization, sublimation and fusion, solubilities and solvation energies, partition coefficients, diffusion constants, viscosities, surface tensions, and liquid and crystal densities. 

The heat capacity, Cp, a useful parameter in evaluating vaporization, sublimation, and fusion enthalpies with temperature, was determined by DSC measurements for 1,3-oxathiane 3,3-dioxide to be 148.1 2.6 J moC at... 

When heated, arsenious sulphide readily sublimes and fusion occurs, according to Borgstrom,8 at 320° C. Earlier determinations have put the melting point at 310°,9 300°10 and 325° C.11 Air must be excluded or oxidation occurs. Some degree of volatilisation may be observed at the ordinary temperature.12 According to Schuller,13 when... 

Heats of Vaporisation, Sublimation and Fusion.s—These latent heats have been obtained from the respective pressure-temperature... 

Atrs H molar enthalpy of a transition between any two phases in general Molar enthalpies of vaporization, sublimation, and fusion are positive. The reverse processes of condensation (gas liquid), condensation or deposition (gas solid), and freezing (liquidssolid) have negative enthalpy changes. 

In Section 11.5, we examined a beaker of liquid water at room temperature from the molecular viewpoint. Now, let s examine a block of ice at —10 °C from the same molecular perspective, paying close attention to two common processes sublimation and fusion. 

Table 6.2 Heats of Fusion, Vaporization, and Sublimation and Specific Heat at...

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