Chapter Menu Lesson 1 Solids Liquids and Gases

Chapter Menu Lesson 1: Solids, Liquids, and Gases Lesson 2: Changes in States of Matter Click on a hyperlink to view the corresponding lesson.

6. 1 Solids, Liquids, and Gases random motion solid liquid gas

6. 1 Solids, Liquids, and Gases What are states of matter? • The state of matter depends on the motion of its particles. • States of matter are solids, liquids, gases, and plasma. States of Matter

6. 1 Solids, Liquids, and Gases What are states of matter? (cont. )

6. 1 Solids, Liquids, and Gases Particles in Matter • All objects are made of particles. • Even though the objects are not moving, their particles are. • Particles move in random motion, or in any direction at any speed.

6. 1 Solids, Liquids, and Gases Particles in Matter (cont. ) • In any object, the number of particles moving in one direction is equal to the number of particles moving in the opposite direction. • Particles collide and change speed and direction.

6. 1 Solids, Liquids, and Gases Particles Attract • Particles are attracted to each other. • The attraction grows stronger as particles move closer together and weaker as they move apart.

6. 1 Solids, Liquids, and Gases Solids • A solid is matter with a fixed shape and fixed volume. • Particles stay in the same place and vibrate back and forth in all directions.

6. 1 Solids, Liquids, and Gases Liquids • A liquid is matter with a fixed volume but not a fixed shape. • The particles are farther apart and not as strongly attracted so they move more freely than in a solid.

6. 1 Solids, Liquids, and Gases • A gas is matter that has no fixed shape or fixed volume. • Shape and volume of a gas depends on the container. • Gas particles move in random motion inside a container.

6. 1 Solids, Liquids, and Gases Familiar States of Matter

6. 1 Solids, Liquids, and Gases 1. 2. 3. 4. A B C D Particles in a ____ are close together and strongly attracted and therefore, can only vibrate. A gas B liquid C solid D plasma

6. 1 Solids, Liquids, and Gases 1. 2. 3. 4. A B C D Why do liquids have a fixed volume, but not a fixed shape? A The particles are strongly attracted to each other and close together. B The particles are attracted to each other but far enough apart they can slide past each other. C The particles are so far apart the attraction is weak and they have random movement. D none of the above

6. 1 Solids, Liquids, and Gases 1. 2. 3. 4. A B C D Which three states of matter are most common on Earth? A solid, liquid, plasma B gas, liquid, plasma C plasma, solid, gas D solid, liquid, gas

6. 2 Changes in States of Matter temperature boiling point thermal energy evaporation melting point condensation freezing point sublimation vaporization deposition boiling

6. 2 Changes in States of Matter Temperature, Thermal Energy, and Heat • Changes in energy can cause matter to change from one state to another. • A change from one state to another is the result of the change in motion of particles in an object and the strength of the forces of the particles in the object. Matter Changing State

6. 2 Changes in States of Matter Moving Particles and Kinetic Energy • Even when an object is not moving, the particles in the object are moving. • The particles have kinetic energy. The gas particles inside the balloon have energy because they are moving.

Moving Particles and Kinetic Energy (cont. )

6. 2 Changes in States of Matter Temperature and Average Kinetic Energy • Temperature is a measure of the average kinetic energy of the particles in a material. • Particles in matter move faster as the temperature increases. lower temperature higher temperature

6. 2 Changes in States of Matter Measuring Temperature • One way to measure temperature is to use a liquid thermometer. • The particles in the liquid move farther apart and cause the liquid to take up more space.

6. 2 Changes in States of Matter Particles of Matter and Potential Energy • Particles in a substance have potential energy. – Potential energy decreases as particles move closer together. – Potential energy increases as particles move farther apart.

6. 2 Changes in States of Matter Particles of Matter and Potential Energy (cont. )

6. 2 Changes in States of Matter Thermal Energy • Thermal energy includes both kinetic and potential energy. • Objects in the gas state have particles that move faster and are farther apart compared to objects in the solid state. • Gas particles have more potential and kinetic energy than particles in a solid. • The thermal energy of the gas state is greater than the solid state for any substance.

6. 2 Changes in States of Matter Adding and Removing Thermal Energy • Heating a pot of water adds thermal energy. • Cooling water in a refrigerator removes thermal energy.

6. 2 Changes in States of Matter Thermal Energy and Changes of State • When kinetic energy is increasing in a substance, the temperature of the substance increases. • When only potential energy is increasing, the substance changes state. How does thermal energy affect the state of a substance?

6. 2 Changes in States of Matter Thermal Energy and Changes of State (cont. )

6. 2 Changes in States of Matter Changes Between the Solid and Liquid States • The difference between water and ice are the movements of the particles and thermal energy the particles contain. • Melting occurs when a solid changes into a liquid. • The melting point of a material is the temperature at which a material changes from solid to liquid.

6. 2 Changes in States of Matter Changes Between the Solid and Liquid States (cont. ) • As thermal energy is added to a solid, the temperature increases until the melting point is reached. • The substance does not increase temperature until it has completely melted.

6. 2 Changes in States of Matter Changes Between the Solid and Liquid States (cont. )

6. 2 Changes in States of Matter Energy Changes During Melting • Even though thermal energy is still being added, the temperature is not changing as a substance melts. • The average kinetic energy of the substance does not change, only the potential energy changes. • The attractive forces become weaker as the particles increase speed and move farther apart.

6. 2 Changes in States of Matter Energy Changes During Melting (cont. )

6. 2 Changes in States of Matter Freezing • Freezing occurs when a liquid changes into a solid. • The freezing point is the temperature at which a liquid changes to a solid. • Thermal energy is removed and the potential energy decreases.

6. 2 Changes in States of Matter Freezing (cont. )

6. 2 Changes in States of Matter Vaporization and Boiling • Boiling water is liquid changing to a gas. • Vaporization is the change from a liquid to a gas. • The particles become too spread out and the attractive forces are too weak to keep the particles close together.

6. 2 Changes in States of Matter Vaporization and Boiling (cont. ) • Vaporization occurs both at the surface and inside the liquid. • Vaporization that occurs within the liquid is called boiling. • Boiling point refers to the temperature that boiling occurs in a substance.

6. 2 Changes in States of Matter Vaporization and Boiling (cont. )

6. 2 Changes in States of Matter Evaporation • Vaporization that occurs at the surface of a liquid is called evaporation. • Evaporation occurs both at the boiling point and temperatures below the boiling point.

6. 2 Changes in States of Matter Pressure and the Boiling Point • The boiling point depends on the pressure exerted on the liquid. • Bubbles in the liquid must form for boiling to occur. • As air pressure increases, it becomes harder for the bubbles to form. • The boiling point increases as air pressure increases.

6. 2 Changes in States of Matter Condensation • Condensation is the change from a gas to a liquid. • Thermal energy is removed from a gas. • The gas particles slow down and move closer together until the attractive forces hold them together and a liquid forms.

6. 2 Changes in States of Matter Condensation (cont. )

6. 2 Changes in States of Matter Adding Thermal Energy • The temperature of the ice increases until the melting point is reached. • The temperature stays constant as the ice melts. • After the ice has melted, the temperature increases until the boiling point is reached. • The temperature stops increasing until all the water has changed to water vapor.

6. 2 Changes in States of Matter Adding Thermal Energy (cont. ) • Adding more thermal energy causes the temperature of the water vapor to increase.

6. 2 Changes in States of Matter Removing Thermal Energy • Water vapor changes back into ice by removing thermal energy.

6. 2 Changes in States of Matter Changes Between Solids and Gases • Sublimation is the change of a solid to a gas without going through the liquid stage. • Thermal energy must be added to a solid. • Dry ice changes from a solid to a gas.

6. 2 Changes in States of Matter Changes Between Solids and Gases (cont. ) • The opposite of sublimation is deposition, the change of a gas to a solid without going through the liquid state. • Thermal energy is removed from a gas. • Water vapor changes directly to ice as frost on leaves.

6. 2 Changes in States of Matter Changes in Energy Among States of Matter

6. 2 Changes in States of Matter 1. 2. 3. 4. A B C D The point at which a liquid changes to a gas is called ____. A melting point B freezing point C condensation point D boiling point

6. 2 Changes in States of Matter 1. 2. 3. 4. A B C D A liquid can change to a gas through ____. A evaporation B freezing C melting D sublimation

6. 2 Changes in States of Matter 1. 2. 3. 4. A B C D Thermal energy must be ____ when a liquid changes to a ____. A lost; gas B gained; solid C lost; solid D increased; solid

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1. 2. 3. 4. A B C D A ____ has no fixed shape but a fixed volume. A gas B liquid C solid D plasma

1. 2. 3. 4. A B C D Gases have ____ and ____. A no fixed shape; fixed volume B fixed shape; no fixed volume C fixed shape; fixed volume D no fixed shape; no fixed volume

1. 2. 3. 4. A B C D The particles in a solid are ____ and ____ compared to the particles in a liquid. A closer together; slower B farther apart; slower C farther apart; faster D closer together; faster

1. 2. 3. 4. A B C D Sublimation occurs when a solid changes into a ____. A liquid B gas C plasma D steam

1. 2. 3. 4. A B C D As air pressure ____, the ____ of a liquid increases. A decreases; boiling point B decreases; freezing point C increases; freezing point D increases; boiling point

SCI 3. e 1. 2. 3. 4. A B C D Which describes particles in a solid? A They are far apart and have weak attractive forces for each other. B They move rapidly and in any direction. C They vibrate in a fixed location. D They have no fixed volume.

SCI 3. e 1. 2. 3. 4. A B C D Why do liquids have no fixed shape? A The particles vibrate in a fixed location. B The particles have a high average kinetic energy. C The particles have a high potential energy. D The particles can slide past each other.

SCI 3. e 1. 2. 3. 4. A B C D Adding thermal energy can ____ or ____. A lower temperature; change the state of matter B increase temperature; lower temperature C increase temperature; change the state of matter D remove kinetic energy; change the state of matter

SCI 3. d 1. 2. 3. 4. A B C D In which state of matter are particles far apart and moving in random motion? A gas B liquid C solid D ice

SCI 3. e 1. 2. 3. 4. A B C D One glass of water has a temperature of 30°C and another glass of water a temperature of 40°C. Which is true? A The glass of water at 30°C has lower average kinetic energy. B The glass of water at 40°C has lower average kinetic energy. C The two glasses have equal average kinetic energy. D none of the above

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