Get ready to play with the submicroscopic world! The Particle Modeler is a playground for experimenting with the building blocks of matter. Drag particles around, then see how they move. Transfer energy in or out of the model or trap them in a container. Watch what happens and discover important ideas about matter. The particles that comprise matter—molecules—are represented in this interactive tool as spheres. They are programmed to react to their placement under the influence of two scientific laws: a law governing molecular forces and the force of gravity.

The behavior of particles governs how the world around us works, but the submicroscopic world of particles is too small to see! Move new particles into the container with your finger. The particles can not overlap each other or the container. Tap on Run and see how the particles behave. Tap on the snowflake to cool the particles down and the sun to heat the particles up. Add a lid to the container to prevent the particles from flying out of the container.

This material is based upon work supported by the National Science Foundation under Grant No. DRL-1621299. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.