## How Gibbs derived the Phase Rule

Originally posted on carnotcycle:

The Phase Rule formula was first stated by the American mathematical physicist Josiah Willard Gibbs in his monumental masterwork On the Equilibrium of Heterogeneous Substances (1875-1878), in which he almost single-handedly laid the theoretical foundations of chemical thermodynamics. In a paragraph under the heading “On Coexistent Phases of Matter”, Gibbs gives…