Matter: Properties and Changes PDF

LESSON 1 Matter: Properties and Changes...

LESSON 1 Matter: Properties and Changes Properties of Matter Key Concept Why do athletes bite their What do you think? Read the two statements below and decide medals? whether you agree or disagree with them. Place an A in the Before column if you agree with the statement or a D if you disagree. After you’ve read this lesson, reread the statements to see if you have changed your mind. Before Statement After The particles in a solid object do not move. Your weight depends on your location. Mark the Text How can a substance’s properties Use an Outline As you read, make an outline to be measured? summarize the information Matter has many different properties. For example, a helmet in the lesson. Use the main you wear while biking is hard and shiny. The water in a stream headings in the lesson as might be cool and clear. Learning about physical properties and the main headings in the outline. Complete the chemical properties will help you to identify many types of outline with the information matter and their uses. under each heading. Physical properties are any characteristics of matter that you can observe without changing the identity of the substances that Academic Vocabulary make it up. Examples of physical properties are state of matter, observe Copyright © McGraw-Hill Education. Permission is granted to reproduce for classroom use. (verb) to watch and notice shape, mass, volume, density, solubility, and temperature. something Mass Some physical properties, such as mass and weight, depend on the size of the sample. Mass is the amount of matter Scientific Vocabulary in an object. property Mass v. Weight Weight is the gravitational pull on an object. (noun) a quality or feature Weight depends on the location of an object. Mass does not. The of something mass of an object is the same on Earth as it is on the Moon. An object’s weight, however, is greater on Earth than it is on the Scientific Vocabulary Moon because Earth’s gravity is stronger than the Moon’s gravitational pull gravity. (noun) the attraction caused by gravity Reading Essentials Matter: Properties and Changes 1 THIS MATERIAL IS PROVIDED FOR INDIVIDUAL EDUCATIONAL PURPOSES ONLY AND MAY NOT BE DOWNLOADED OR FURTHER DISTRIBUTED.  Modeling Mass Mass can be modeled by representing the particles in a substance. The more particles in a substance, the greater the mass of the substance, as shown in the figure below. 15 grams 5 grams Volume Like mass and weight, the volume of an object is a physical property. Volume is the amount of space a substance takes up. It depends on the size of the sample. You can measure Scientific Vocabulary the volume of a liquid by pouring it into a measuring cup or a graduated cylinder graduated cylinder. You can measure the volume of a solid in (noun) a tube that has two ways. If a solid has a regular geometric shape, multiply its lines on the side and is length, width and height together. You can find the volume of a used to measure the solid with an irregular shape by using the displacement method. volume of liquids A graduated cylinder is filled part way with water. The volume of water is noted. The solid is then placed in the cylinder. The Scientific Vocabulary volume of the solid is the difference between the water level irregular (adjective) not even or before and after placing the solid in the water. The common unit smooth for liquid water is the milliliter (mL). Modeling Volume An observable volume can be represented Scientific Vocabulary by the shape of the substance. The larger the shape, the more Copyright © McGraw-Hill Education. Permission is granted to reproduce for classroom use. displacement volume the substance has, as shown in the figure below. (noun) the amount of water moved by an object when it is placed in water 30 mL 10 mL 2 Matter: Properties and Changes Reading Essentials THIS MATERIAL IS PROVIDED FOR INDIVIDUAL EDUCATIONAL PURPOSES ONLY AND MAY NOT BE DOWNLOADED OR FURTHER DISTRIBUTED.  How can a substance’s mass and volume be used to identify a substance? Mass and volume are related. This relationship can be expressed by another physical property. Density This physical property of matter is called density. Density is the mass of a substance divided by the volume of the substance. It does not depend on the size or amount of the sample. Look at the slope of the graph in the figure below. As the mass increases, the volume increases by an equivalent amount. The density of a substance never changes. Density 10 9 8 7 6 Mass (g) 5 4 3 2 1 0 0 2 4 6 8 10 12 14 16 18 20 Volume (cm³) Copyright © McGraw-Hill Education. Permission is granted to reproduce for classroom use. Density and States of Matter Solids are the densest state of matter because the particles are very close together. In liquids, particlesRE_P320_101A_NGMSS-BANK are farther apart. Liquids are less dense than solids, but are much denser than gases. Gases have very low densities because the particles are far apart and move freely. Academic Vocabulary Calculating Density Understanding the relationship between calculate mass and volume will help you calculate density. (verb) to use numbers to find out something Density Equation Density ​ ___(g) mass (g) ​  mL ​ ​​ = ​​ __________ volume (mL) ​​ m D = ​_​  v_​​ A sample of a substance, regardless of its size, will always have the same density. Reading Essentials Matter: Properties and Changes 3 THIS MATERIAL IS PROVIDED FOR INDIVIDUAL EDUCATIONAL PURPOSES ONLY AND MAY NOT BE DOWNLOADED OR FURTHER DISTRIBUTED.  How can a substance be identified based on how it changes? Matter can change physically and chemically. Some changes in matter change the identity of the substance. Chemical Properties Substances undergo chemical reactions when they change into other substances. A chemical property is a characteristic of matter that can be observed as it changes to a different type of matter. Flammability Some substances, such as wood and paper, are flammable. Flammability is the ability of a type of matter to burn easily. Flammability is a chemical property. Oxidation You have probably seen objects, such as old cars, that have begun to rust. Rust is a substance that forms when iron reacts with oxygen and water in the air. The ability to rust is a chemical property of iron or metals that contain iron. Rusting is a type of oxidation. Oxidation is the reaction of a substance with an oxidizing agent, changing it into a new substance. Reaction to Acid Many substances react with acid. Reactivity occurs when a substance reacts with another substance, changing it into a new substance. How can a substance’s properties be used to identify a substance? Academic Vocabulary Look at the table of substances and their physical properties. identify You can identify the unknown substance by comparing its (verb) to recognize and physical properties to the physical properties of the known name a thing or person substances. Copyright © McGraw-Hill Education. Permission is granted to reproduce for classroom use. Substance Color Mass g Melting Density Point °C g/cm3 Table salt white 14.5 801 2.17 Sugar white 11.5 148 1.53 Baking white 16.0 50 2.16 soda Unknown white 16.0 801 2.17 4 Matter: Properties and Changes Reading Essentials THIS MATERIAL IS PROVIDED FOR INDIVIDUAL EDUCATIONAL PURPOSES ONLY AND MAY NOT BE DOWNLOADED OR FURTHER DISTRIBUTED.  All the substances are white. So, you cannot identify the unknown substance by its color. You cannot identify it by its mass. Mass is a property that changes with the amount of the sample. However, melting point and density do not depend on the size or amount of the sample. The unknown substance has the same melting point and density as table salt, so it must be table salt. Identifying a Substance Using Properties Both physical properties and chemical properties are used for identifying and sorting (classifying) materials. You probably often sort materials by their properties without realizing it. Objects are usually sorted based on the physical and chemical properties they have in common. Word Origin Conductivity, melting and boiling points, and solubility are solubility some physical properties that can be useful for sorting matter From Latin solubilis, and identifying substances. means “capable of being dissolved” Conductivity Some materials conduct electricity. Conductivity is the ability to conduct electricity or thermal energy. Melting and Boiling Point Each material has a melting point and a boiling point. Melting point and boiling point do not depend on the size or the amount of the material. The melting point is the temperature at which a solid changes to a liquid. The boiling point is the temperature at which a liquid changes to a gas. Melting point and boiling point are physical properties. Solubility You can observe another physical property of matter when a solid, such as sugar, dissolves in water. To dissolve means “to mix evenly.” Solubility (sahl yuh BIH luh tee) is the ability of one material to dissolve in another material. Copyright © McGraw-Hill Education. Permission is granted to reproduce for classroom use. Reread the statements at the beginning of the lesson. Fill in the After column with an A if you agree with the statement or a D if you disagree. Did you change your mind? Reading Essentials Matter: Properties and Changes 5 THIS MATERIAL IS PROVIDED FOR INDIVIDUAL EDUCATIONAL PURPOSES ONLY AND MAY NOT BE DOWNLOADED OR FURTHER DISTRIBUTED.