CHEM102 Lecture Notes - Bravais Lattice, Amorphous Solid, Crystallin

• School: University of Alberta
• Department: Chemistry
• Course: CHEM102
• Professor: All

Document Summary

Introductory university chemistry i (chem 101 / 103) Crystalline solid is a solid where the atoms, ions, or molecules are in order and well- defined arrangements. Amorphous solid is a solid whose particles have no orderly structure. There are five different types of crystalline solids: Very hard, very high melting point (graphite is soft) A crystalline solid can be represented by a three-dimensional array of points called a crystal lattice. Unit cell is the smallest unit of a crystal which on repeating in a three-dimensional manner generates the whole crystal. Here is another unit cell of the pattern. Coordination number of a particle in a crystal is the number of nearest particles surrounding it. Coordination number of the central particle = 6. There are 7 crystal systems and 14 types of unit cells that occur in nature. We focus on the cubic system which has 3 types of unit cells.