|Science Focus Topic 4 Notes: Expansion & Contraction||| Print ||
As the average energy of particles increases, the spaces between the particles increases. They expand
(increase their volume) as the temperature increases. As the average energy of particles decreases, the spaces
between the particles decreases. They contract (decrease their volume) as the
Pure substances are matter that are made up of only one kind of particle, which can be a solid liquid or
Expansion and Contraction in Solids
Solids can become longer or shorter depending on the temperature (average energy of the particles).
Table 1 (p. 211) gives precise measurements of different solid materials at different temperatures.
Expansion and Contraction in Gases
When the particles in a gas are heated, their average energy increases and they need more room, so they expand.
When the particles in a gas are cooled, the volume decreases, or contracts, because the particles need less room.
Under extremely high temperature conditions (like the temperatures inside the Sun, particles
can be split into what makes them up (electrons and ions). This creates a fourth state of matter called plasma.