1 Three States of Matter

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1 CHAPTER 3 1 Three States of Matter SECTION States of Matter BEFORE YOU READ After you read this section, you should be able to answer these questions: What is matter made of? What are the three most common states of matter? How do behave in each state of matter? National Science Education Standards PS 1a What Are the Three States of Matter? Have you ever had a steaming hot bowl of soup and an ice cold drink for lunch? The three most common states of matter are found in this lunch. The soup and the drink are made of water. However, the water exists in three different forms. The soup and the drink are liquids. The ice is a solid. The steam from the soup is a gas. The substance is the same whether it is a solid, a liquid, or a gas. The substance is just in a different form, or state. The states of matter are the physical forms of a substance. The three well-known states of matter are solid, liquid, and gas. Matter is made up of very tiny. These are called atoms and molecules. Atoms and molecules act differently in each state of matter. We cannot see atoms and molecules, but they are always moving. How fast they move depends on the state they are in. The figure below describes the three states of matter and how act in each state. STUDY TIP Describe Write a short description of a solid, a liquid, and a gas. Include the motions of the and how the motion affects volume and shape. READING CHECK 1. Define What are states of matter? Models of a Solid, a Liquid, and a Gas Particles of a solid have a strong attraction between them. The are closely locked in position and only vibrate. Particles of a liquid are more loosely connected than those of a solid and can move past one another. Particles of a gas move fast enough that they overcome the attractions between them. The move independently and collide frequently. TAKE A LOOK 2. Identify In which state do the move about the most? In which state do they move about the least? Interactive Textbook 41 States of Matter

2 SECTION 1 Three States of Matter continued READING CHECK 3. Describe How do the of a solid move? STANDARDS CHECK PS 1a A substance has characteristic properties, such as density, a boiling point, and solubility, all of which are independent of the amount of the sample. A mixture of substances often can be separated into the original substances using one or more of the characteristic properties. 4. Identify How are the in a liquid different from the in a solid? What Are the Properties of Solids? Any solid material, such as a penny, a rock, or a marble, has a specific shape and volume. For example, if you place a solid marble into a bottle, the marble s shape and volume stay the same. It keeps its original shape and volume no matter where it is placed. A solid is the state of matter that has a specific shape and volume. The of a solid are very close to each other. They have a strong attraction for each other. Therefore, the of a solid are locked into place. However, they do make small movements called vibrations. Remember, the of any substance are always in motion. What Are the Properties of Liquids? Ice cubes and liquid water are made of the same material, but they are physically very different. In solids, such as ice cubes, are closely locked together and vibrate in place. In liquids, such as liquid water, are able to move more freely. A liquid is a substance that has a specific volume, but doesn t have a particular shape. For example, a liter of milk takes the shape of its container. The same liter of milk will take the shape of a bowl it is poured into. The shape of the milk changes. The volume of the milk stays the same. This is seen in the figure below with the juice. In a liquid, the move fast enough to overcome their attraction to each other. As a result, they can move or slide past each other, even though they always stay close together. In liquids, we know that the can move past each other because liquids can change shape. Although their shapes are different, the beaker and the graduated cylinder each contain 355 ml of juice. Interactive Textbook 42 States of Matter

3 SECTION 1 Three States of Matter continued THE UNIQUE PROPERTIES OF LIQUIDS Liquids have special properties that the other states of matter do not have. One special property of liquids is surface tension. Surface tension is a force that acts on the at the surface of a liquid. Water has a high surface tension, causing it to form spherical or oval-shaped drops. You may have seen beads of water on an object. Each liquid has a different amount of surface tension. Gasoline has a low surface tension and forms flat drops. Another special property of liquids is viscosity. Viscosity is a liquid s resistance to flow. Liquids that are sticky usually have a high viscosity. The in these liquids have a strong attraction for each other. For example, honey flows more slowly than water. So the viscosity of honey is greater than that of water. What Are the Properties of Gases? The properties of a gas are different from the properties of other states of matter. A gas has no specific shape or volume. All gases take on the shape of the container they are put in. This is because their have little attraction for each other. A gas that you might know about is helium. Helium is the gas that is used to fill birthday balloons. When the helium is in the tank, the are close to each other. As the helium fill a balloon, they spread out. So the amount of space between the helium in the balloon increases. READING CHECK 5. Describe What is surface tension? Critical Thinking 6. Apply Concepts Put the following in order from lowest to highest viscosity: syrup, water, and cream. Many balloons can be filled from one tank of helium because the of helium gas in a balloon are far apart. TAKE A LOOK 7. Describe What happens to the space between when helium moves from the tank into the balloon? Interactive Textbook 43 States of Matter

4 Section 1 NSES PS 1a SECTION VOCABULARY gas a form of matter that does not have a definite volume or shape liquid the state of matter that has a definite volume but not a definite shape solid the state of matter in which the volume and shape of a substance are fixed states of matter the physical forms of matter, which include solid, liquid, and gas surface tension the force that acts on the surface of a liquid and that tends to minimize the area of the surface viscosity the resistance of a gas or liquid to flow 1. Identify Name the three states of matter and give an example of each. 2. Identify What is one property that all of matter have in common? 3. Compare How are the of a liquid different from the of a solid? 4. Compare How are the of a liquid different from the of a gas? 5. Identify What property of water causes it to form beads on the leaves of the plants? 6. Describe Indicate how the shape and volume of each state of matter are different. State of matter Definite shape Definite volume solid liquid no gas no Interactive Textbook 44 States of Matter

5 Physical Science Answer Key continued SECTION 2 PHYSICAL PROPERTIES 1. properties that can be observed and measured without making a new substance 2. its mass or weight, its density, its compressibility 3. the amount of matter in a given volume times as much, or 44 g more 5. D m V D 28 g 19.3 g/cm cm 6. when measured at the same temperature and pressure 7. zinc 8. If it is denser than water, it will sink. 9. The diet soda objects less dense than water float in the water. 10. the liquid with the lowest density 11. a change that affects the physical properties of a substance 12. melting 13. a change of state 14. A gas can change into a liquid or into a solid. 15. nothing 1. Divide the mass of the substance by its volume. 2. No, because all the substances are more dense than methanol. 3. D m V D 135 g 2.7 g/cm cm aluminum 4. The ball with the smaller volume has the larger density. 5. Its volume must get larger. SECTION 3 CHEMICAL PROPERTIES 1. change into new matter 2. iron 3. The identity of the substance does not change when the physical property is observed; when the chemical property is observed, the substance changes identity. 4. Gasoline its properties match the properties in the table. 5. a change that produces a new substance 6. its bad smell 7. The cake has different properties than its ingredients do. 8. color change, change in texture, odor given off, heat absorbed or released 9. A new substance is not made. 10. chemical changes 1. A chemical property of a substance describes the chemical change that can happen to the substance. 2. When a substance reacts, it changes into a new substance. For the property to be a physical property, the substance must be the same after it has undergone the change. 3. heat 4. Type of change Description of change Chemical Physical Physical Chemical rusting boiling freezing burning 5. a color change, a change in texture, an odor given off, heat absorbed or liberated 6. Chemical change a color change indicates that a chemical change has taken place. 7. Heat felt above the flame: chemical change Smoke: chemical change Melted wax: physical change Chapter 3 States of Matter SECTION 1 THREE STATES OF MATTER 1. the physical forms of a substance 2. They move about the most in the gas state and the least in the solid state. 3. They vibrate. 4. They move past each other. 5. a force that acts on the at the surface of a liquid 6. water, cream, syrup 7. There is more space between. 1. Solid: brick, penny, ice cube Liquid: water, milk, soda, oil Gas: air, oxygen, water vapor 2. They are always moving. Interactive Textbook Answer Key 69 Physical Science

6 Physical Science Answer Key continued 3. The of a liquid can move past one another, but the of a solid stay in fixed positions. 4. The of a gas can move far away from one another, but the of a liquid stay close to one another. 5. surface tension 6. State of matter Definite shape Definite volume Solid yes yes Liquid no yes Gas no no SECTION 2 BEHAVIOR OF GASES 1. a measure of how fast the of an object are moving 2. when it is heated 3. Temperature of gas Energy of gas 1) 20 C Particles have the smallest amount of energy. 2) 50 C Particles have more energy than at 20 C, but not as much as at 80 C. 3) 80 C Particles have the largest amount of energy. Volume of gas Volume is smallest. Volume is larger than at 20 C but smaller than at 80 C. Volume is largest. 4. the amount of force that is put on an area 5. temperature and pressure 6. It is one-third as much. 7. It is one-half as much. 1. temperature, volume, and pressure 2. The balloon goes from a warm temperature in the house to a cold temperature outside. The volume of the balloon will decrease outside because the gas move more slowly and exert less pressure. The air in the balloon take up less space L; according to Charles s law, at constant pressure, volume is directly related to temperature. 4. The volume will double. According to Boyle s law, at constant temperature, volume is inversely related to pressure. 5. The volume, temperature, and pressure of a gas are all related. If there is a change in one, it will affect the others as well. SECTION 3 CHANGES OF STATE 1. energy 2. It changes into a gas, or evaporates, or vaporizes. 3. energy 4. the temperature at which it changes from a solid to a liquid C 6. The sweat removes energy from your body as it evaporates. 7. boil 8. beaker of boiling water 9. Water from a lake evaporates, then it condenses to become part of a cloud. 10. evaporation 11. The warmer temperatures cause the water droplets to evaporate. 12. It changes directly from a solid to a gas. 13. The graph is flat, or horizontal. This means that the temperature is constant. 1. The of a solid only vibrate. The of a liquid can move past one another. The of a gas are free to move anywhere. 2. Energy is added or removed during a change of state. A change of state does not make a new substance, so changes of state are physical changes. 3. Melting requires energy. Freezing is the removal of energy. Both happen at the same temperature. 4. Both processes change a liquid to a gas. Evaporation is a slower process than boiling. In an open container, you need to heat a liquid in order to boil it. 5. Sublimation requires energy and changes a solid directly to a gas. Condensation gives off energy and changes a gas to a liquid. 6. Property Solid Liquid Gas Attraction between Distance between Movement of strong weaker than in a solid little or no attraction close close far apart They vibrate only. They can move past each other. There is freedom of movement. Interactive Textbook Answer Key 70 Physical Science