1. 1 Types of Solids Chap. 13: Day 4b

2. 2 Metallic and Ionic Solids Sections 13.6-8

3. 3 Properties of Solids 1. 1. Molecules, atoms or ions locked into a CRYSTAL LATTICE 2. Particles are CLOSE together 3. STRONG IM forces 4. Highly ordered, rigid, incompressible ZnS, zinc sulfide

4. 4

5. 5 Types of Solids Table 13.6 TYPE FORCE Properties. Ionic Ionic Hard, brittle, High MP poor conductor poor conductor Metallic Electrostatic Malleable, Range of MP good conductor good conductor Molecular Dipole Soft, Low of MP Ind. Dipole poor conductor Ind. Dipole poor conductor NetworkExtended Range of MP & hardness covalent poor conductor covalent poor conductor

6. 6 Network Solids Diamond Graphite

7. 7 A comparison of diamond (pure carbon) with silicon.

8. 8 Atom Packing in Unit Cells Assume atoms are hard spheres and that crystals are built by PACKING of these spheres as efficiently as possible.

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11. 11 Crystal Lattices Regular 3-D arrangements of equivalent LATTICE POINTS in space. Lattice points define UNIT CELLS –smallest repeating internal unit that has the symmetry characteristic of the solid.

12. 12 Cubic Unit Cells of Metals Figure 13.24 Simple cubic (SC) Body- centered cubic (BCC) Face- centered cubic (FCC)

13. PROPERTIES OF LIQUIDS Chap. 13: Day 4a

14. Intermolecular Forces The forces BETWEEN molecules. Holds the molecules together. At a set temperature: What phase has the strongest force? Solids What phase has the weakest forces? Gases (vapor)

15. Viscosity the resistance of a fluid to flow Thick fluids have high viscosity

16. Vapor Pressure The pressure exerted by a vapor in equilibrium with its liquid state. The pressure at which liquid changes to vapor Liquids with high vapor pressures turn into vapors very easily. (Volatile) Ex. Gasoline, perfume

17. Once equilibrium is reached, the vapor particles will begin to condense back to a liquid

18. Boiling Point The temperature at which the vapor pressure of the liquid equals the atmospheric pressure The entire liquid is changing state, not just the surface. Water boils at 100 0 C at standard P

19. Vapor Pressure vs Temperature

22. Liquid Properties Surface Tension- Ability of liquid molecules to hold on to each other. Apparent “skin” affect Ex. Over filling a liquid in a glass with out the liquid spilling

23. Hg

25. Liquid Properties Capillary Rise- the tendency of a liquid to rise in a small diameter tube due to the surface tension of the liquid.

27. I NTERMOLECULAR F ORCES STRONG Forces lead to…. Nonvolatile Substances High boiling points Low evaporation rates Low vapor P at room temperature WEAK Forces lead to..  Volatile substances  Low boiling points  High evaporation rates  High vapor P at room temperature