‘Changing the state of matter’ considers the transformations states of matter undergo from one form to another during the processes of freezing, boiling, dissolving, and mixing. All such transformations and the corresponding equilibria that are reached in state transitions can be expressed in terms of the chemical potential and the pushing power it represents. Changes in temperature and pressure can lower or raise boiling and freezing points. Josiah Gibbs' phase rule is concerned with the equilibria between various forms of matter. Phase diagrams help chemists draw conclusions about the compositions of mixtures, minerals, and alloys. Transitions in solutions, including osmosis, and solid-to-solid phase transitions are also discussed.