| A | B |
|---|
| Melting point | the temperature at which a solid changes into a liquid. |
| Freezing point | the temperature at which a liquid changes into a solid. |
| crystal | the particles are arranged in an orderly, repeating, three-dimensional pattern |
| unit cell | may be simple cubic, body-centered cubic, or face-centered cubic. In the space-filling models and line drawings, the spheres represent atoms or ions. |
| allotropes | A solid substances can exist in more than one form. Ex Diamond and graphite |
| amorphous solid | A solid that lacks an ordered internal structure. |
| glass | A transparent fusion product of inorganic substances that have cooled to a rigid state without crystallizing. |
| Crystal Systems | Depend on the angles at which the faces of a crystal intersect are always the same for a given substance and are characteristic of that substanc |
