1 / 18

CHAPTER 13

CHAPTER 13. Kinetic Molecular Theory (K.M.T.). Kinetic Theory: The tiny particles in all forms of matter are in constant motion. Explains the properties of solids, liquids, & gases. SOLIDS. Solids and K.M.T. More closely packed than liquids or gases.

lesterlewis
Download Presentation

CHAPTER 13

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CHAPTER 13 Kinetic Molecular Theory(K.M.T.)

  2. Kinetic Theory: • The tiny particles in all forms of matter are in constant motion. • Explains the properties of solids, liquids, & gases.

  3. SOLIDS • Solids and K.M.T. • More closely packed than liquids or gases. • Intermolecular forces are VERY effective. • Only vibrational movement. • Crystalline vs. Amorphous (glass) solids.

  4. Properties of Solids • Definite shape and volume • Melting point: • Crystalline Solids: Definite melting point, KE of particles overcome attractive forces of solid. • Amorphous Solids: No definite melting point, Supercooled liquids. 3. High Density and Incompressibility 4. Low diffusion rate: very slow

  5. Crystalline Solids 1. Crystal structure = 3D arrangement of particles of crystals. 2. Unit Cell = smallest portion of a crystal that shows the 3D structure.

  6. GASES 1. no definite shape or volume 2. Particles are small, hard spheres, with insignificant volume (very far apart). 3. Particles move rapidly in constant random motion 4. All collisions are perfectly elastic (Energy is transferred & not lost) 5. There are no forces of attraction or repulsion between gas particles. • Gas Pressure: is the result of simultaneous collisions of billions of gas particles with an object.

  7. Gas Pressure: is the result of simultaneous collisions of billions of gas particles with an object. • Vacuum: when no gas particles are present • Atmospheric Pressure: results from the collisions of air molecules with objects. Decreases as you climb a mountain b/c air layer around earth thins out at high elevations.

  8. Barometer:measures atmospheric pressure • SI unit of pressure = pascal (Pa) • Atm pressure at sea level = STP (0oC) = 101.3 kPa = 760 mm Hg= 1 atm= 760 torr= 29.92 inHg = 14.7 psi Ex: 1.50 atm = ? kPa 1.50 atm 101.3 kPa = 1.52 x 102kPa 1 atm

  9. UNITS OF PRESSURE

  10. Barometers

  11. LIQUIDS: Why are they the least common state of matter? 1. Liquids and K.M.T. • Are particles in constant motion? Spacing? Kinetic Energy? Attractive forces? • Fluid: a substance that flows and hence takes the shape of its container.

  12. Properties of Liquids • High Density: 1000x greater than gases, 10% less dense than solids. • Relatively Incompressible: Water’s volume only decreases 4% under 1000atm of pressure! • Can diffuse: Slower in liquids than gases due to: slower motion and attractive forces.

  13. Atmospheric Pressure & Boiling Point

  14. Evaporation (vaporization): conversion of a liquid to a gas or vapor below its boiling point. • Vapor Pressure: particles collide with the walls of the sealed container. • Dynamic Equilibrium • Boiling Point: temp. at which the v.p. of the liquid is just equal to the external pressure.

  15. Evaporation vs. Boiling

  16. Phase Change Diagrams You will see a heat curve for water in the next slide.

  17. HEAT OF FUSION 80 cal/g HEAT OF VAPORIZATION 540 cal/g EVAPORATION, VAPORIZATION Gas CONDENSATION DEPOSITION Liquid SUBLIMATION MELTING FREEZING, SOLIDIFICATION, CRYSTALLIZATION Solid

  18. HEAT OF FUSION 80 cal/g HEAT OF VAPORIZATION 540 cal/g EVAPORATION, VAPORIZATION Gas CONDENSATION DEPOSITION Liquid SUBLIMATION MELTING FREEZING, SOLIDIFICATION, CRYSTALLIZATION Solid

More Related