Kinetic Theory and Diffusion

arrangement of particles in states of matter

changes of state

• freezing and melting
• - when a substance is heated, energy is being transferred to the particles of the substance, making them vibrate. the more the particles vibrate, the weaker the bonds between the particles become so the particles can move around more, detemining their new state.
• - when a substance is cooled, particles loose energy which prevents them from vibrating. the less the particles vibrate the strong the bonds between them become and the less the particles are able to move so the substance would be close to a solid.
• when a substance goes from a liquid to gas, it can go one of two ways ; boiling and evaporating
• How boiling is different to evaporating:
• boiling-
• requires a certain temperature
• requires heat
• bubbles of gaseous particles are formed
• occurs throughout entire substance
• evaporation-
• can occur at all temperatures
• no bubbles are formed
• occurs only at the surface of substance