States of Matter (Particle Model)
Why particles move differently in solids, liquids, gases.
The kinetic molecular theory explains states of matter through the energy and arrangement of particles.
Temperature is a measure of average kinetic energy โ heat drives all changes of state.
Try it โ particle motion
Three (or four) states
In a solid, particles are held in fixed positions by strong attractive forces and can only vibrate on the spot โ that's why a solid keeps its own shape and volume. In a liquid, those forces are weaker, so particles stay close together but can slide past one another โ the substance takes the shape of its container while keeping a fixed volume. In a gas, the forces are almost negligible compared to the particles' kinetic energy, so they fly apart and fill any space available, spreading out to fit the whole container. Plasma is a 4th state that appears at huge temperatures, when collisions are so violent that electrons are stripped from atoms entirely, leaving a soup of charged particles.