# Chapter 3 Lesson 1 Solids liquids and gases

• Slides: 19

Chapter 3 Lesson 1 “Solids, liquids and gases”

I. States of Matter A. 3 States of matter 1. Solids -wood, steel, plastic, ice 2. Liquids -water, orange juice, gasoline 3. Gases -helium, water vapor, neon

B. Kinetic Theory of Matter 1. Def – all particles are in constant motion 2. Higher temperature = more movement -ex: water vs. boiling water

C. Solids 1. Def – an object that has a definite shape and definite volume. -shape stays consistent -can’t make smaller or larger 2. Drawing of solid 3. Particles are held tightly together

4. Types of Solids a. Crystalline Solid -repeating geometric pattern -ex: snowflake, salt, sugar b. Non-crystalline/Amorphous Solid -non-repeating geometric pattern -ex: glass, plastics, wax

D. Liquids 1. Def – a material that has the ability to flow and take the shape of its container. 2. Definite volume but indefinite shape. 3. Drawing of Liquid 4. Ex: water, milk, gasoline 5. Particles are held loosely together and have the ability to move around each other or be mixed.

E. Gases 1. Material that always takes the shape of its container. 2. Indefinite shape and indefinite volume 3. Drawing of a gas 4. Particles are not held together. 5. Ex: Air, Neon, Helium, Hydrogen

II. Thermal Expansion A. Def – matter expands when it gets warmer and contracts when it gets cooler. 1. Ex: roads, bridges, thermometers 2. Metal ball and hoop demonstration

Chapter 3 Lesson 2 “The Gas Laws” Gas Review 1. Indefinite shape 2. Indefinite volume 3. Takes shape of container 4. Fast moving particles (1600 km/hr)

I. Pressure A. Def – the amount of force exerted over an area. 1. Tires – gases push on the outside walls of tires B. Formula - P = F / A C. Measured in Pascals (N/m 2) 1. 101. 3 k. Pa at Sea level

II. Boyle’s Law (Pressure and Volume Law) A. Def – When the volume of a gas is decreased the pressure goes up. When the volume of a gas is increased the pressure goes down. 1. Temp. must remain constant 2. P 1 x V 1 = P 2 x V 2

III. Charles’ Law (Temperature Law) A. Def – The volume of a gas increases with temperature (energy). The volume of a gas decreases with a loss of temperature (energy). 1. Energy (heat) causes gases to move faster more pressure on container. 2. Loss of heat causes gases to move slower less pressure on container. 3. V 1 = V 2 T 1 T 2 4. Temp. must be in Kelvins!!

IV. Combined Gas Law A. Combines all aspects B. Formula P 1 x V 1 P 2 x V 2 = T 1 T 2

Practice Problems 1. A gas has a volume of 5. 0 L at a pressure of 50 k. Pa. What happens to the volume when the pressure is increased to 125 k. Pa? The temp does not change. 2. Gas stored in a tank at 273 K has a volume of 10. 0 L. If the temperature goes up to 305 K, what would the new volume of the tank need to be? 3. At 275 K, the gas in a cylinder has a volume of 0. 25 L. The gas is allowed to expand to 0. 29 liters. What must the final temperature of the gas be assuming pressure stays the same? 4. A gas at 310 K has a pressure of 100 k. Pa and a volume of 20. 0 L. If the temperature increases to 350 K and the volume remains constant, what is the new pressure of the gas? (Use Combined Gas Law)

Chapter 3 Lesson 3 “Changes in State”

I. Changing States A. Diagram Handout 1. Phase Change – A reversible physical change that occurs when a substance changes from one state to another.

2. Process Start Finish Example Melting Solid Liquid Ice to water Freezing Liquid Solid Water to ice Vaporization Liquid Gas Water to steam Condensation Gas Liquid Dew in the morning Sublimation Solid Gas Ice cubes shrinking Deposition Gas Solid Frost on windows

3. Other Changes a. Evaporation – liquid changes to a gas below the boiling point. -ex: Getting out of a pool. Water evaporates but does not boil. 4. Energy Change a. Endothermic – energy is absorbed -athletic ice pack b. Exothermic – energy is released -Mg + HCl

II. Heat and State Changes A. Heat of Fusion 1. Def - The amount of energy needed to change a material from the solid state to the liquid state. 2. Water 334 k. J/kg B. Heat of Vaporization 1. Def – The amount of energy needed to change a material from the liquid state to the gaseous state. 2. Water 2260 k. J/kg