Section 12-1 The Kinetic-Molecular Theory Kinetic-molecular theory explains the different properties of solids, liquids, and gases, and describes particle behavior in terms of particles in motion Atomic composition affects chemical & physical properties

Section 12-1 The Kinetic-Molecular Theory (cont.) GAS Gases consist of small particles separated by empty space. Gas particles are too far apart to experience significant attractive or repulsive forces.

Section 12-1 The Kinetic-Molecular Theory (cont.) Gas particles are in constant random motion. An elastic collision is one in which no kinetic energy is lost.elastic collision

Section 12-1 The Kinetic-Molecular Theory (cont.) Kinetic energy of a particle depends on mass and velocity. Temperature is a measure of the average kinetic energy of the particles in a sample of matter.Temperature Absolute Zero = -273 o C or 0 K

Section 12-1 Explaining the Behavior of Gases Great amounts of space exist between gas particles. Compression reduces the empty spaces between particles.

Section 12-1 Gas Pressure Pressure is defined as force per unit area.Pressure Gas particles exert pressure when they collide with the walls of their container.

Section 12-1 Gas Pressure (cont.) The particles in the earth’s atmosphere exert pressure in all directions called air pressure. There is less air pressure at high altitudes because there are fewer particles present, since the force of gravity is less.

Section 12-1 Gas Pressure (cont.) Barometers are instruments used to measure atmospheric air pressure.Barometers

Section 12-1 Gas Pressure (cont.) Manometers measure gas pressure in a closed container.

Section 12-1 Gas Pressure (cont.) The SI unit of force is the newton (N). One pascal(Pa) is equal to a force of one Newton per square meter or N/m 2.pascal One atmosphere is equal to 760 mm Hg or kilopascals (kPa).atmosphere

Section 12-1 Gas Pressure (cont.) Pg. 407

A.A B.B C.C D.D Section 12-1 Section 12.1 Assessment The average of kinetic energy of particles in a substance is measured by its ____. A.mass B.density C.temperature D.pressure

Section 12-2 Intermolecular Forces Attractive forces between molecules cause some materials to be solids, some to be liquids, and some to be gases at the same temperature.

Section 12-2 Intermolecular Forces (cont.) Dipole-dipole forces are attractions between oppositely charged regions of polar molecules.Dipole-dipole forces

Section 12-2 Intermolecular Forces (cont.) Hydrogen bonds are special dipole-dipole attractions that occur between molecules that contain a hydrogen atom bonded to a small, highly electronegative atom with at least one lone pair of electrons, typically fluorine, oxygen, or nitrogen.Hydrogen bonds

IMF Hydrogen Bonds H bonded to N, O or F (type of dipole-dipole) Dipole-Dipole ∂ - end attracted to a ∂+ end of a polar molecule Induced Dipole (aka dispersion force) VERY weak attraction between non-polar covalent molecules

Section 12-2 Intermolecular Forces (cont.)

A.A B.B C.C D.D Section 12-2 Section 12.2 Assessment A hydrogen bond is a type of ____. A.dispersion force B.ionic bond C.covalent bond D.dipole-dipole force

A.A B.B C.C D.D Section 12-2 Section 12.2 Assessment Which of the following molecules can form hydrogen bonds? A.CO 2 B.C 2 H 6 C.NH 3 D.H 2

Section Liquids and Solids Liquids: are closely packed in a fixed volume, not in a fixed position. are much denser than gases because of the stronger intermolecular forces holding the particles together need large amounts of pressure to compress into very small amounts.

Section 12-3 Liquids (cont.) Fluidity is the ability to flow and diffuse; liquids and gases are fluids. Viscosity is a measure of the resistance of a liquid to flow and is determined by the type of intermolecular forces, size and shape of particles, and temperature.Viscosity

Section 12-3 Liquids (cont.) Surface tension is the energy required to increase the surface area of a liquid by a given amount.Surface tension Surfactants are compounds that lower the surface tension of water.Surfactants

Section 12-3 Liquids (cont.) Cohesion is the force of attraction between identical molecules. (WATER  WATER) Adhesion is the force of attraction between molecules that are different. (WATER  CONTAINER) Capillary action is the upward movement of liquid into a narrow cylinder, or capillary tube.

Section Liquids and Solids Solids: contain particles with strong attractive intermolecular forces that vibrate in a fixed position. are more dense than liquids. An exception-Ice is not more dense than water.

Plasma- The Fourth State of Matter Greater than C Collisions break up atoms to make positive ions and electrons. Most of the universe is plasma

A.A B.B C.C D.D Section 12-3 Section 12.3 Assessment The viscosity of a liquid will increase as: A.particle size decreases B.temperature decreases C.intermolecular forces decrease D.particle size increases

Section Phase Changes That Require Energy p. 425

Section 12-4 Phase Changes That Require Energy (cont.) The melting point of a crystalline solid is the temperature at which the forces holding the crystal lattice together are broken and it becomes a liquid.melting point Molecules are freer to move as solid  liquid  gas

Section 12-4 Phase Changes That Require Energy (cont.) p. 426 Once over the hump of KE, substance can vaporize

Section 12-4 Phase Changes That Require Energy (cont.) Vaporization is the process by which a liquid changes to a gas or vapor.Vaporization Evaporation is vaporization only at the surface of a liquid.Evaporation

Section 12-4 Phase Changes That Require Energy (cont.) In a closed container, the pressure exerted by a vapor over a liquid is called vapor pressure.vapor pressure In closed container, water leaving/ entering is equal

Section 12-4 Phase Changes That Require Energy (cont.) The boiling point is the temperature at which the vapor pressure of a liquid equals the atmospheric pressure.boiling point

Section 12-4 Phase Changes That Require Energy (cont.) Sublimation is the process by which a solid changes into a gas without becoming a liquid.

Section 12-4 Phase Changes That Release Energy As heat flows from water to the surroundings, the particles lose energy. The freezing point is the temperature at which a liquid is converted into a crystalline solid.freezing point FYI: Melting point and freezing point are the same points, just opposite direction of phase change

Section 12-4 Phase Changes That Release Energy (cont.) As energy flows from water vapor, the velocity decreases. The process by which a gas or vapor becomes a liquid is called condensation. condensation Deposition is the process by which a gas or vapor changes directly to a solid, and is the reverse of sublimation.Deposition

Section 12-4 Phase Diagrams A phase diagram:phase diagram graph of pressure versus temperature shows in which phase a substance will exist under different conditions of pressure and temperature.

Section 12-4 Phase Diagrams (cont.) The triple point is the point on a phase diagram that represents the temperature and pressure at which all three phases of a substance can coexist.triple point p. 429

Section 12-4 Phase Diagrams (cont.) The phase diagram for different substances are different from water. p. 430

A.A B.B C.C D.D Section 12-4 Section 12.4 Assessment The addition of energy to water molecules will cause them to ____. A.freeze B.change to water vapor C.form a crystal lattice D.move closer together

A.A B.B C.C D.D Section 12-4 Section 12.4 Assessment The transfer of energy from one object to another at a lower temperature is ____. A.heat B.degrees C.conductivity D.electricity

Assignment #1 DUE ON Friday, March 19 th –Includes the worksheet labeled assignment #1 –Also, the following textbook problems: Q18, 23, 27, 31-35, 58, 63, 68, 69, 79, 82

Resources Menu Chemistry Online Study Guide Chapter Assessment Standardized Test Practice Image Bank Concepts in Motion

Study Guide 1 Section 12.1 Gases Key Concepts The kinetic-molecular theory explains the properties of gases in terms of the size, motion, and energy of their particles. Dalton’s law of partial pressures is used to determine the pressures of individual gases in gas mixtures. Graham’s law is used to compare the diffusion rates of two gases.

Study Guide 2 Section 12.2 Forces of Attraction Key Concepts Intramolecular forces are stronger than intermolecular forces. Dispersion forces are intermolecular forces between temporary dipoles. Dipole-dipole forces occur between polar molecules.

Study Guide 3 Section 12.3 Liquids and Solids Key Concepts The kinetic-molecular theory explains the behavior of solids and liquids. Intermolecular forces in liquids affect viscosity, surface tension, cohesion, and adhesion. Crystalline solids can be classified by their shape and composition.

Study Guide 4 Section 12.4 Phase Changes Key Concepts States of a substance are referred to as phases when they coexist as physically distinct parts of a mixture. Energy changes occur during phase changes. Phase diagrams show how different temperatures and pressures affect the phase of a substance.

A.A B.B C.C D.D Chapter Assessment mm Hg is equal to ____. A.1 Torr B.1 pascal C.1 kilopascal D.1 atmosphere

A.A B.B C.C D.D Chapter Assessment 2 A collision in which no kinetic energy is lost is a(n) ____ collision. A.net-zero B.elastic C.inelastic D.conserved

A.A B.B C.C D.D Chapter Assessment 3 Solids with no repeating pattern are ____. A.ionic B.crystalline C.liquids D.amorphous

A.A B.B C.C D.D Chapter Assessment 4 What is the point at which all six phase changes can occur? A.the melting point B.the boiling point C.the critical point D.the triple point

A.A B.B C.C D.D Chapter Assessment 5 What are the forces that determine a substance’s physical properties? A.intermolecular forces B.intramolecular forces C.internal forces D.dispersal forces

A.A B.B C.C D.D STP 1 What do effusion rates depend on? A.temperature of the gas B.temperature and pressure of the gas C.molar mass of the gas D.molar mass and temperature of the gas

A.A B.B C.C D.D STP 2 A sealed flask contains helium, argon, and nitrogen gas. If the total pressure is 7.5 atm, the partial pressure of helium is 2.4 atm and the partial pressure of nitrogen is 3.7 atm, what is the partial pressure of argon? A.1.3 atm B.6.1 atm C.1.4 atm D.7.5 atm

A.A B.B C.C D.D STP 3 Adding energy to a liquid will: A.cause it to form crystal lattice B.decrease the viscosity C.compress the particles closer together D.increase the velocity of the particles

A.A B.B C.C D.D STP 4 Hydrogen bonds are a special type of ____. A.ionic bond B.covalent bond C.dipole-dipole force D.dispersion force

A.A B.B C.C D.D STP 5 How many atoms of oxygen are present in 3.5 mol of water? A.2.1 x B.3.5 x C.6.02 x D.4.2 x 10 24

IB Menu Click on an image to enlarge.

IB 1

IB 2

IB 3

IB 4

IB 5

IB 6

IB 7

IB 8

IB 9

IB 10

IB 11

IB 12

IB 13

IB 14

IB 15

IB 16

IB 17

IB 18

IB 19

IB 20

CIM Table 12.4Unit Cells Table 12.5Types of Crystalline Solids Figure 12.30Phase Diagrams

Help Click any of the background top tabs to display the respective folder. Within the Chapter Outline, clicking a section tab on the right side of the screen will bring you to the first slide in each respective section. Simple navigation buttons will allow you to progress to the next slide or the previous slide. The “Return” button will allow you to return to the slide that you were viewing when you clicked either the Resources or Help tab. The Chapter Resources Menu will allow you to access chapter specific resources from the Chapter Menu or any Chapter Outline slide. From within any feature, click the Resources tab to return to this slide. To exit the presentation, click the Exit button on the Chapter Menu slide or hit Escape [Esc] on your keyboards while viewing any Chapter Outline slide.

End of Custom Shows This slide is intentionally blank.