Related Experiment Video
Updated: Oct 2, 2026

Phase Diagram Characterization Using Magnetic Beads as Liquid Carriers
Published on: September 4, 2015
The estimation of melting points and fusion enthalpies using experimental solubilities, estimated total phase change
James S Chickos1, Gary Nichols, Paul Ruelle
1Department of Chemistry, University of Missouri-St. Louis, Missouri 63121, USA. jsc@umsl.edu
Abstract:
Melting points and fusion enthalpies are predicted for a series of 81 compounds by combining experimental solubilities in a variety of solvents and analyzed according to the theory of mobile order and disorder (MOD) and using the total phase change entropy estimated by a group additivity method. The error associated in predicting melting points is dependent on the magnitude of the temperature predicted. An error of +/- 12 K (+/- 1 sigma) was obtained for compounds melting between ambient temperature and 350 K (24 entries). This error increased to +/- 23 K when the temperature range was expanded to 400 K (46 entries) and +/- 39 K for the temperature range 298-555 K (79 entries). Fusion enthalpies were predicted within +/- 2sigma of the experimental values (+/- 6.4 kJ mol(-1)) for 79 entries. The uncertainty in the fusion enthalpy did not appear dependent on the magnitude of the melting point. Two outliers, adamantane and camphor, have significant phase transitions that occur below room temperature. Estimates of melting temperature and fusion enthalpy for these compounds were characterized by significantly larger errors.
More Related Videos
Related Concept Videos
Phase Transitions: Melting and Freezing
Phase Transitions: Sublimation and Deposition
Phase Changes
A substance melts or freezes at a temperature called its melting point and boils or condenses at its boiling point. These temperatures depend on pressure. High pressure favors the denser form of the substance, so typically, high pressure...
Solubility
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules, atoms, and/or ions)...
Enthalpy of Solution
Liquid–Solid Solutions

