The kinetic theory of matter describes the arrangement, motion, and behavior of particles in different states.
When observing tiny smoke particles suspended in air through a microscope, the particles are seen to move continuously in a random, zig-zag fashion.
Identify the term used to describe this random movement of suspended particles.
Explain how the motion of the smoke particles provides direct evidence for the kinetic model of gases.
The table below summarizes key physical properties of substances in three different phases:
| Phase | Shape | Density |
|---|---|---|
| Solid | Maintains a constant, defined shape | High |
| Liquid | Adapts to the shape of the container's base | High |
| Gas | Expands to occupy the entire volume and shape of its vessel | Very low |
Explain these macroscopic observations by describing the spacing, arrangement, and motion of the constituent particles in solids, liquids, and gases.
51 exam-style questions on Edexcel IGCSE Physics Ideal gas molecules. Each one has a worked solution and a mark scheme showing where the marks go.