Entropy of fusion

The entropy of fusion is the increase in entropy when melting a substance. This is almost always positive since the degree of disorder increases in the transition from an organized crystalline solid to the disorganized structure of a liquid; the only known exception is helium. It is denoted as Δ S fus {displaystyle Delta S_{ ext{fus}}} and normally expressed in J mol−1 K−1 The entropy of fusion is the increase in entropy when melting a substance. This is almost always positive since the degree of disorder increases in the transition from an organized crystalline solid to the disorganized structure of a liquid; the only known exception is helium. It is denoted as Δ S fus {displaystyle Delta S_{ ext{fus}}} and normally expressed in J mol−1 K−1 A natural process such as a phase transition will occur when the associated change in the Gibbs free energy is negative. Since this is a thermodynamic equation, the symbol T refers to the absolute thermodynamic temperature, measured in kelvins (K). Equilibrium occurs when the temperature is equal to the melting point T = T f {displaystyle T=T_{f}} so that