Chapter 13 States of Matter 13.1 The Nature of Gases 13.2 The Nature of Liquids 13.3 The Nature of Solids 13.4 Changes of State Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Kinetic Theory and a Model for Gases Do Now: Which of the three states of matter has most energy? Why? What are some properties of gases? Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Kinetic Theory and a Model for Gases Kinetic Theory of Gases SIZE: - tiny particles (so small, considered to have no size relative to each other) far away from each other no attraction or repulsion Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Kinetic Theory and a Model for Gases Kinetic Theory of Gases MOTION: Particles are in constant, rapid, and random motion. When they collide no energy is lost (elastic collisions) When they collide with the walls of a container, they cause pressure. https://phet.colorado.edu/en/simulation/gas-properties Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Kinetic Theory and a Model for Gases Kinetic Theory of Gases ENERGY: - Kinetic Energy of gases is determined by: KE = 1/2 mv2 M= mass v= velocity - Temperature is a measure of the average kinetic energy of the gas particles. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Vacuum: empty space with no particles and no pressure. Gas Pressure Gas pressure results from the force exerted by a gas per unit surface area of an object. Vacuum: empty space with no particles and no pressure. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Pressure: Measured using: Barometer Gas Pressure Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
The SI unit of pressure is the pascal (Pa). Gas Pressure The SI unit of pressure is the pascal (Pa). Normal atmospheric pressure is 101.3 kPa. Two older units of pressure are commonly used. millimeters of mercury (mm Hg) atmospheres (atm) Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Gas Pressure One standard atmosphere (atm) is the pressure to support 760 mm of mercury in a mercury barometer at 25°C. 1 atm = 760 mm Hg = 101.3 kPa. STP is 0°C and a pressure of 101.3 kPa, or 1 atm. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Converting Between Units of Pressure Sample Problem 13.1 Converting Between Units of Pressure A pressure gauge records a pressure of 600 kPa. Convert this measurement to a. atmospheres b. millimeters of mercury Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Calculate Solve for the unknowns. Sample Problem 13.1 Calculate Solve for the unknowns. 2 Multiply the given pressure by the conversion factor. b. 600 kPa × = 4501 mm Hg 101.3 kPa 760 mm Hg 1 atm a. 600 kPa × = 5.9 atm Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Kinetic Energy and Temperature Average Kinetic Energy Gas particles are always moving Their speed depends on the mass of particles On average lighter gases move FASTER than heavier gases (have same average kinetic energy so they need higher velocity to make up for less mass) Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Interpret Graphs Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Kinetic Energy and Temperature Average Kinetic Energy The average kinetic energy of the particles in a substance is directly related to the substance’s temperature. Absolute zero (0 K, or –273.15oC) is the temperature at which the motion of particles theoretically ceases. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
Kinetic Energy and Temperature Average Kinetic Energy and Kelvin Temperature The Kelvin temperature of a substance is directly proportional to the average kinetic energy of the particles of the substance. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.
END OF 13.1 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.