The PhET Collection at the University of Colorado has two simulations designed to introduce the states of matter and phase changes.
- States of Matter Basics operates in two modes: States lets you select different materials in solid, liquid, and gaseous forms and show how they respond to heating and cooling; Phase Changes lets you control temperature, volume, and pressure for a selection of materials and show them transitioning between states.
https://phet.colorado.edu/en/simulation/states-of-matter-basics
- States of Matter takes the Basics simulation above and adds a third option, exploring interaction energies. Note that the simulated "reaction chamber" will explode if you exceed its design parameters, much like a real one!
https://phet.colorado.edu/en/simulation/states-of-matter
- Additionally, this simple animation at JavaLab allows students to see how internaal motion changes with state