CHM 11500 Lecture Notes - Lecture 27: Cubic Crystal System, Sodium Chloride

• School: Purdue University
• Department: Chemistry
• Course: CHM 11500
• Professor: Chittaranjan Das

Document Summary

Chm 155 - lecture 27 - crystal structures. When many liquids cool, they freeze to form crystalline solids. Crystalline solids are solids in which the particles are arranged in a definite repeating pattern. Some crystalline solids consist of one crystal (such as diamonds or salt particles) while other crystalline solids are conglomerations of many crystals (such as chunks of ice or metals) Amorphous solids are the opposite of crystalline solids: their particles do not move readily while freezing and so become frozen in random positions resulting in a disordered internal structure. Amorphous solids include glass, wax, and plastics. There are several types of crystalline solids: A unit cell is the repeating unit that creates the organized pattern present in a crystalline solid. A space lattice is the collection of all the points in a crystal that have identical environments . The unit cell is the portion of the space lattice that will generate the entire lattice if repeated.