http://www.ck12.org Chapter 13. States of Matter
13.3 Solids
Lesson Objectives
- Describe a solid according to the kinetic-molecular theory.
- Understand that a solid also has a vapor pressure, and describe the relationship between the vapor pressure of
a solid and sublimation. - Describe the features of the seven basic crystal systems.
- Define a unit cell.
- List the four classes of crystalline solids and describe the properties of each.
- Describe an amorphous solid.
Lesson Vocabulary
- amorphous solid
- crystal
- deposition
- melting point
- sublimation
- unit cell
Check Your Understanding
Recalling Prior Knowledge
- How does the kinetic-molecular theory treat the condensed states of matter differently than it treats gases?
- What happens to the particles of a liquid as they undergo a change of state into a gas?
So far, we have studied gases and liquids. In this lesson, you will gain an understanding of the nature of solids,
focusing on the many different ways in which particles can be arranged within ordered solid crystals.
Properties of Solids
Solids are similar to liquids in that both are condensed states, with particles that are far closer together than those
of a gas. However, while liquids are fluid, solids are not. The particles of most solids are packed tightly together
in an orderly arrangement. The motion of individual atoms, ions, or molecules in a solid is restricted to vibrational
motion about a fixed point. Solids are almost completely incompressible, and for most substances, their solid form
is the densest of the three states of matter.