Crystallization of Supersaturated Sodium Acetate - Demonstration

A supersaturated solution of sodium acetate is poured onto a small sodium acetate crystal, and the liquid crystallizes immediately upon contact in an exothermic process.

The probe from a digital thermometer touches the solid sodium acetate to test the temperature. It is seen that the material is quite warm. The process of crystallization is an exothermic process in which heat is given off to the surroundings.

Discussion: 

The crystallization occurred rapidly once a seed crystal was available. The seed crystal provides a structure around which the ions of sodium acetate could form a solid crystal lattice.

Credits: 
  • Design, Demonstration and Production
    • John W. Moore University of Wisconsin - Madison, Madison, WI 53706
    • Lynn R. Hunsberger University of Louisville, Louisville, KY 40292
    • Steven D. Gammon University of Idaho, Moscow, ID 83843
  • Text
    • Kelly Houston Jetzer University of Wisconsin - Madison, Madison, WI 53706
    • John W. Moore University of Wisconsin - Madison, Madison, WI 53706