Thermal Energy and Molecular Motion

The simulation shows how adding or removing heat influences the motion of molecules in the three states of matter. In a solid, molecules vibrate around fixed points; in a liquid they slide past each other and can convect when heated from below; in a gas they move freely at speeds that increase with temperature.

Students step through numbered scenes using the on‑screen buttons or keyboard shortcuts. They can apply Heat, Off, or Cool to a solid block, a liquid in a closed tank, and a gas, watching vibrations grow, convection currents form, and molecular speeds change. Later steps let them touch a hot metal object and release it to feel how energy transfers to a cooler hand.

By interacting with the model, learners visualise the microscopic basis of temperature, understand why hot objects feel hot, and see the role of convection in liquids, reinforcing core thermodynamics concepts.