The particle model of matter, then pure substances, mixtures and separating them. Concept tutorials for introducing or revising each idea, with particle simulations.
Matter is made of particles: their arrangement, motion and attraction explain the properties of solids, liquids and gases (AC9S7U05).
All matter is made of tiny particles with empty space between them, always moving and attracting each other. Match particle diagrams to solids, liquids and gases.
Describe the arrangement, motion and attraction of particles in a solid, a liquid and a gas, and use them to explain why solids keep their shape and gases fill their containers.
Use particle theory to explain physical properties (how easily a substance squashes, its density, how it flows) by naming the arrangement, motion or attraction behind each one.
Melting and boiling need energy put in: the particles move faster and pull free of each other. Freezing and condensing give energy out. While a substance is changing state, its temperature stays the same, because the energy goes into separating the particles, not speeding them up.
The particle model treats matter as tiny particles that move and attract each other. It explains states, diffusion, compressing gases and expansion very well. It can't explain colour, why substances react, or electricity, because it treats particles as plain balls with no parts. Scientists keep a model for what it does well and use other models for the rest.
One kind of particle or many, and how differences in properties let us separate mixtures (AC9S7U06).
A pure substance contains only one kind of particle; a mixture contains two or more. Classify familiar materials by their particles, not by how they look.
Every separation technique uses a difference in a physical property between the parts of a mixture. Match property differences to techniques, and choose the order.
Filtration separates a solid that hasn't dissolved; evaporation recovers a solid that has. Describe both, name the residue and filtrate, and choose the right one.
Distillation collects a liquid by boiling and condensing it; chromatography separates dissolved substances such as dyes. Explain each principle and when distillation beats evaporation.
A few quick questions on choosing and justifying a separation technique, and saying why another one would not work. Taught in class; use this to check yourself.
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