Drawing Particle Diagrams
Draw and interpret particle diagrams — dot representations showing the arrangement, spacing, and movement of particles in solids (close, regular, vibrating in place), liquids (close, random, flowing past each other), and gases (widely spaced, moving rapidly in all directions) — and use these diagrams to explain observable properties such as fixed shape, fixed volume, and compressibility
What a learner can do afterwards
- Draw labelled particle diagrams for solids, liquids, and gases showing the correct arrangement and spacing of particles
- Use their particle diagram to explain why solids keep their shape but liquids flow
- Sketch what happens to particles during a change of state (e.g. melting) and explain the energy changes involved
The lesson
Everything around you, even the air, is made of tiny bits called particles. They are far too small to see. Scientists draw particles as dots to show how they are arranged. This kind of drawing is called a particle diagram.
In a liquid, particles are still close together, but they are not lined up neatly. They tumble and slide past each other, so a liquid can flow and pour into any shape of container.
Jake blows up a balloon. Inside, gas particles are spread far apart and zoom around in every direction, bouncing off the balloon walls. Because there is so much empty space between them, Jake can squeeze the balloon and push the particles closer together.
When something melts, like ice turning to water, its particles gain energy from heat. They vibrate faster until they break free from their fixed spots and start to slide past each other, so the solid becomes a liquid!
Particle diagrams show how close, how ordered, and how much particles move, and that tells you whether something is a solid, a liquid, or a gas.
Watch it
Where it sits
Learn first
Nothing; this is a starting point.
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.