States of Matter
Matter – all the substances and materials from which the physical universe is composed
Kinetic Particle Theory – a theory which accounts for the bulk properties of matter in terms of the constituent particles. It states that:
- All matter is made up of tiny, moving particles, invisible to the naked eye. Different substances have different types of particles (atoms, molecules or ions).
- The particles move all the time. The higher the temperature, the faster they move and the forces of attraction weaken
- Heavier particles move more slowly than lighter particles at a given temperature
Diffusion – the process by which different substances mix as a result of the random motions of their particles. Particles with smaller Mr diffuses faster.
Intimate mixing – when diffusion takes place between a liquid and a gas
Brownian Motion – random motion of particles caused by smaller and faster moving water particles constantly colliding with them and moving them around
When the object is melting or vaporising, heat energy is being added but temperature is not changing. The average kinetic energy stays the same. Energy changes to potential energy by separating.
Absolute Zero – the theoretical temperature (which can never be reached) at which all particle motion stops. Absolute zero is -273°C or 0 Kelvin. To calculate Kelvin = °C + 273. A 1K change equals a 1°C change.