Phase Diagrams from Kitchen Chemistry

John Brady
Smith College
Author Profile


The main pdf file describes a series of lab or lecture activities using water, salt, ice, sugar, and alcohol that can be used to help students understand simple phase diagrams. The supporting pdf file contains larger images of the phase diagrams for use as a pdf slide show or for printing handouts.

Used this activity? Share your experiences and modifications



This is designed for a sophomore or junior level required course in petrology.

Skills and concepts that students must have mastered

Students should have had an introduction to phase diagrams and have taken an intro chemistry course.

How the activity is situated in the course

This is a stand-alone exercise meant to help students understand phase diagrams.


Content/concepts goals for this activity

The goal of this activity is to have students use and understand phase diagrams.

Higher order thinking skills goals for this activity

Other skills goals for this activity

Description of the activity/assignment

An ability to read and use simple igneous phase diagrams is a major goal of most undergraduate courses in petrology. Many students have difficulty attaining this goal because phase diagrams are an unfamiliar kind of graph and they are described in most textbooks with an unfamiliar language

Determining whether students have met the goals

Students have successfully met the goals if they demonstrate a better understanding of how to read and interpret a phase diagram.

More information about assessment tools and techniques.

Teaching materials and tips

Other Materials