1. Water

2. Ice Liquid water’s density is greatest 4 o C. Ice has a 10% greater volume; therefore, lower density.

3. Ice

4. Why does ice behave so differently? As kinetic energy (speed of the molecules) decreases, hydrogen bonds hold water molecules in place. The water molecules are held in an open framework creating a hexagonal symmetry of molecules. This increases the volume.

5. Aqueous Solutions Water samples that contain dissolved substances. Solvent - dissolving medium Solute - dissolved particles Example - salt water - NaCl is the solute and the water is the solvent Characteristics: –Homogeneous –Stable –They do not settle out –Both solvent and solute will pass through a filter

6. Describe the process of solvation. Watch the next 2 video clips and then answer the above question.

9. Other solution questions: What substances don’t dissolve in water? Why? Why does grease dissolve in gasoline and not water? How does soap work? How is the relationship summed up?

10. Electrolytes Compounds that conduct an electric current in aqueous solution or molten state. All ionic compounds are electrolytes

11. nonelectrolytes Do not conduct an electric current in aqueous solution or molten Many molecular compounds are nonelectrolytes –Ex sugar, rubbing alcohol Some very polar molecules become electrolytes when dissolved in water. Why? Because they ionize in solution –HCl + H 2 O --> H 3 O + + Cl - Weak electrolyte - only a fraction of solute exists as ions Strong electrolyte - large portion of the solute exists as ions

12. Heterogeneous Aqueous Systems 1. Difference in types of heterogeneous aqueous systems is particle size Suspensions - 1.particles settle out of solution 2.can be filtered ex muddy water Colloids - 1. particles stay suspended in dispersion medium 2. many are cloudy - may look clear when diluted 3. exhibit Tyndall effect - scattering of light ex - paints, glues, gelatin desserts, etc Solutions - we already went over solutions

13. Colloidal Systems Emulsions - Colloidal dispersion of liquids in liquids needs an emulsifying agent ex - soap

14. Demo Time