Science Focus Topic 1 Notes: Matter on the Move

Fluid Properties & The Particle Model (Theory)

The particle model helps to explain why gases and liquids flow, while solids do not.

- All substances are made of tiny particles
- All particles in a pure substance are the same (Different pure substances are made of different particles)
- All the particles have spaces between them
- All the particles are always in motion (the speed of the particles increases/decreases when the temperature increases/decreases)
- The particles in a substance are attracted to one another (the strength of the attraction depends on the type of particle)


gas	liquid	solid
assumes the shape and volume of its container	takes the shape of the part of the container which it occupies	retains a fixed volume and shape
particles can move past one another	particles can move/slide past one another	rigid - particles vibrating in place
compressible	not easily compressible	not easily compressible
lots of free space between particles	little free space between particles	little free space between particles
flow easily past each other, move in all directions, do not flow to the lowest possible level	can be poured (always flowing to the lowest possible level) and form a level (flat) surface at rest	form a pile when they are poured (the particles do not continue to flow apart from each other)

Changes of State

A change of state occurs when the particles of a substance gain or lose energy. The diagram below indicated the terminology used.

Applications

- The most common form of matter in our universe exists in a fluid state called plasma, which is a gaslike mixture of positively and negatively charged particles. (It is often considered to be the fourth state of matter) - Plasma, if controlled could be used as rocket fuel.

- Morphing is a special film effect that mimics the changes we see in the states of matter (like terminator - when the policeman morphs into liquid)