1. Solids Image:Wikimedia Commons User Alchemistry-hp

2. Types of Solids  Crystalline Solids: highly regular arrangement of their components  Amorphous solids: considerable disorder in their structures (glass, plastic).

3. Representation of Components in a Crystalline Solid Lattice: A 3-dimensional system of points designating the centers of components (atoms, ions, or molecules) that make up the substance.

4. Bragg’s Law xy + yz = n and xy + yz = 2d sin   n = 2d sin 

5. Crystal Structures - Cubic SimpleFace-CenteredBody-Centered **Knowledge of specific types of crystal structures and the study of the specific varieties of crystal lattices for ionic compounds is beyond the scope of this course and the AP Exam.

6. Crystal Structures - Monoclinic Simple End Face-Centered

7. Crystal Structures - Tetragonal Simple Body-Centered

8. Crystal Structures - Orthorhombic SimpleEndFace-CenteredBodyCenteredFaceCentered

9. Crystal Structures – Other Shapes Rhombohedral Triclinic Hexagonal

10. Closest Packing: Single Layer Photographer : Thierry Dugnolle

11. Closest Packing: Multiple Layers Model: Packing uniform, hard spheres to best use available space. This is called closest packing. Each atom has 12 nearest neighbors.

12. Metal Alloys  Substitutional Alloy: some metal atoms replaced by others of similar size. brass = Cu/Znbrass = Cu/Zn

13. Metal Alloys (continued)  Interstitial Alloy: Interstices (holes) in closest packed metal structure are occupied by small atoms. steel = iron + carbonsteel = iron + carbon

14. Network Atomic Solids Some covalently bonded substances DO NOT form discrete molecules. Diamond, a network of covalently bonded carbon atoms Graphite, a network of covalently bonded carbon atoms

15. Molecular Solids Strong covalent forces within molecules Weak covalent forces between molecules Sulfur, S 8 Phosphorus, P 4