1. Chemistry Chapter 13 Notes #4 Liquids and Solids

2. Liquids Fixed volume, no fixed shape Much more dense than gases –Can still be compressed Liquids and gases can be classified as fluids Liquids can diffuse thru each other like gases do

3. Liquids - Properties Viscosity –Measure of the resistance of a fluid to flow –The greater the viscosity, the slower the flow –Bigger the molecules, slower the flow –Viscosity decreases with increased temps

4. Liquids - Properties Surface Tension –Energy required to increase the surface area of a liquid by a given amount –Surfactants = compounds that lower surface tension (Ex. Dish soap in water)

5. Liquids - Properties Capillary action –In a small tube water forms a meniscus –Caused by cohesion and adhesion –Cohesion = attraction btwn identical molecules –Adhesion= attraction btwn different molecules

6. Solids Fixed volume and fixed shape Solids are NOT fluids Most solids are more dense than most liquids Crystalline solids = atoms are rearranged in an orderly, geometric, 3-dimensional fashion Amorphous solids = no pattern

7. Crystalline solids Atomic Molecules Covalent Network Solids Ionic Compounds Metallic Solids –All have a regular repeating patterns in their structure

8. Amorphous Solids Means “without shape” Often occurs because very hot “molton” liquids cool very quickly so that there is not enough time for crystals to form Ex –Rubber –Glass –plastics