Students investigate how low temperature causes water vapor to condense into a liquid and then freeze to form a solid.

Balance electric charges to prevent Tommy from slipping into icy water. You are presented with 4 particles, each with a charge value. Using the plus/minus scrollbar, you can change the value of the highlighted charge. Then press the play...

Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water. These...