Assessment Chapter Test B Elements, Compounds, and Mixtures USING KEY TERMS Use the terms from the following list to complete the sentences below. Each term may be used only once. Some terms may not be used. solvent solute alloys solution mixture suspensions compound metalloids 1. A pure substance made of two or more elements that are chemically combined is called a. MIXs2 2. If a spoonful of salt is mixed in a glass of water, the salt is the 3. Solid solutions of metals or nonmetals dissolved in metals are 4. A colloid has the properties of solutions and 5. Particles of two or more substances that are distributed evenly among each other form a(n) UNDERSTANDING KEY IDEAS Write the letter of the correct answer in the space provided. 6. Which of the following is a chemical property? MIXs1 a. flammability c. melting point b. density d. ductility 7. How is a mixture different from a compound? MIXs3 a. Mixtures have two or more components. b. Each substance in a mixture keeps its characteristic properties. c. Mixtures are commonly found in nature. d. Solids, liquids, and gases can form mixtures. 8. The particles in both a suspension and a colloid can MIXs3 a. scatter light. b. settle out. c. be soluble. d. pass through a fine filter. Holt Science and Technology 47 Elements, Compounds, and Mixtures
Chapter Test B continued 9. When materials combine to form a mixture, they MIXs3 a. keep their original properties. b. react to form a new substance with new properties. c. combine in a specific ratio. d. always change their physical state. 10. Explain why compounds are considered pure substances. MIXs2 11. How are metalloids different from metals? MIXs1 12. Describe three ways to dissolve solids faster and explain why each works. MIXs3 CRITICAL THINKING 13. Most fresh water in Saudi Arabia is produced by removing salt from sea water. One method involves distillation. Explain how sea water could be purified by distillation, and tell whether it is a chemical or physical process. MIXs3 14. Suppose you were given an unknown liquid and asked to determine if it was an element, a compound, or a mixture. What would you do? How would this help you find out what it was? MIXs1,s2,s3 Holt Science and Technology 48 Elements, Compounds, and Mixtures
Chapter Test B continued 15. After testing three substances, a scientist has recorded the following data. Are these substances the same or different? How can you tell? MIXs1 Physical Property Substance1 Substance 2 Substance 3 Boiling point 2,750 C 2,467 C Density 2.702g/cm 3 7.874g/cm 3 Color Silvery Silvery white Melting point 660.25 C 660.25 C Hardness 2.75 4 2.75 Other Non-magnet Non-magnet INTERPRETING GRAPHICS Use the graph to answer questions 16 and 17. 0.025 Solubility in Water Versus Pressure for Two Gases at 25 C Solubility in water 0.02 0.015 0.01 0.005 Oxygen Nitrogen 0 1 2 3 4 5 Pressure (atm) 6 16. What is the relationship between pressure and the solubility of oxygen and nitrogen in water? MIXs3 17. Which gas experiences a greater change in solubility per unit pressure? MIXS3 Holt Science and Technology 49 Elements, Compounds, and Mixtures
Chapter Test B continued CONCEPT MAPPING 18. Use the following terms to complete the concept map below: pure substances physical or chemical chemical solutions suspensions compounds. MIXs1, 2, 3 Matter can exist as a. mixtures such as which include elements b. c. d. that cannot be that can be such as such as broken down separated water vapor in air blood by by e. f. processes Holt Science and Technology 50 Elements, Compounds, and Mixtures
TEACHER RESOURCE PAGE Section Quizzes SECTION: ELEMENTS 1. B 5. C 2. E 6. B 3. A 7. D 4. D 8. C SECTION: COMPOUNDS 1. A 4. B 2. C 5. A 3. D SECTION: MIXTURES 1. E 6. J 2. H 7. F 3. B 8. D 4. C 9. G 5. I 10. A Chapter Test A 1. B 13. C 2. C 14. A 3. B 15. B 4. A 16. C 5. C 17. D 6. A 18. E 7. B 19. A 8. D 20. B 9. A 21. F 10. D 22. D 11. D 23. A 12. B Chapter Test B 1. compound 2. solute 3. alloys 4. suspensions 5. solution 6. A 7. B 8. A 9. A 10. Answers will vary. Sample answer: Compounds are considered pure substances because they are composed of only one type of particle. The particles of a compound are made of atoms of two or more elements that are chemically combined. Different samples of any compound have the same elements in the same proportion. 11. Answers will vary. Sample answer: Metalloids, also called semiconductors, are elements that have properties of both metals and nonmetals. Some metalloids are shiny, while others are dull. They are only somewhat malleable and ductile. Some metalloids, like silicon, are good electrical conductors only when mixed with other elements. 12. Answers will vary. Sample answer: Mixing by stirring or shaking causes the particles to separate from one another and spread out more quickly among the solvent particles. Heating causes particles to move more quickly. The solvent particles can separate the solute particles and spread them out more quickly. Crushing the solute increases the amount of contact it has with the solvent. The particles of the crushed solute mix with the solvent more quickly. 13. Answers will vary. Sample answer: Salt water is a mixture, so its components can be separated by physical methods. Distillation involves heating the water, which changes water into steam. When salt water is distilled, steam is condensed back into water, and salt is left behind. 14. Answers will vary. Sample answer: I would first try to separate it by using distillation and a centrifuge. If I could separate it this way, I would know that it was a mixture. I would also try to separate it by passing an electric current though it. If I could separate it this way, I would know it was a compound. If I could not separate it at all, I might think it was an element, but I might also need to try other methods of separating it to be sure. 15. Answers will vary. Sample answer: Substances 1 and 3 are probably the same because they have the same melting point, the same amount of hardness, and are nonmagnetic. Substance 2 is different because it has a different density and hardness. It is also a slightly different color. 16. As pressure increases, the solubility of oxygen and nitrogen in water increases. Holt Science and Technology 103 Elements, Compounds, and Mixtures
TEACHER RESOURCE PAGE 17. Oxygen experiences a greater change in solubility per unit pressure. The slope of the line that represents oxygen is steeper. 18. a. pure substances, b. compounds, c. solutions, d. suspensions, e. physical or chemical, f. chemical Chapter Test C 1. B 2. C 3. B 4. B 5. C 6. B 7. D 8. B 9. A 10. C 11. D 12. B 13. A 14. D 15. B 16. C 17. distillation 18. nitrogen 19. nonmetals 20. ratio Standardized Test Preparation READING Passage 1 1. A 3. C 2. H Passage 2 1. B 3. D 2. H INTERPRETING GRAPHICS 1. D 3. B 2. F 4. G MATH 1. C 2. I 3. B 4. I Vocabulary Activity 1. solubility 2. colloid 3. solvent 4. concentration 5. element 6. mixture 7. compound 8. density 9. metalloid 10. alloy 11. solute 12. metal 13. suspension 14. solution 15. nonmetal 16. pure substance F S O L U B I L I T Y L O Z F S J O H E C U F L A M T Y E C O K I L T N E M E L E B I H O D O P R U N E T R O J I N S N E I M E L T Z R N I O P M O C N M O N A C E O P C S J D A E S S O L V E N T G O N U N R N I D N E L P S W L L P S U C T T X R S Y A V U A L M T O A R Y E U K C S T T A O X D P R A O T P U R I E E P I A E M B T L A M X O M S N M D V J O A I L W K N N K C R E D E M C T O A L O O L S U S P E N S I O N E C N A T S B U S E R U P U Q SciLinks Activity 1. Answers will vary. Sample answer: dissolve, do not settle out, solute. 2. Answers will vary. Sample answer: sugar in coffee, tea, salt water. 3. Answers will vary. Sample answer: particles distributed, easily settle out filterable particles. 4. Answers will vary. Sample answer: soup, jello, paints. 5. Answers will vary. Sample answer: large particles, settle out very slowly, can not be filtered. 6. Answers will vary. Sample answer: salad dressing, whipping cream, milk. 7. Answer should show the relationships among 10 of the terms listed in answers 1 6. Holt Science and Technology 104 Elements, Compounds, and Mixtures