Section 1
Fixed vs. Fluid Forms
Key Idea
Matter behaves differently depending on its state. A solid object, like a rock, maintains a rigid structure and holds its specific shape regardless of its container.
In contrast, a liquid possesses the ability to flow. It yields to gravity, spreading out to take the shape of the bottom of its container. These observable differences—holding shape versus taking shape—are the first clues to identifying the state of matter.