Chapter 2 Reading Guide

Transcription

1 Chapter 2 Reading Guide Name Period Unit 1 HW 1 Worksheet (Goals 1 6) SECTION 2.1 PROPERTIES of MATTER (pages 34 37) This section helps you identify the characteristics of matter and substances. It teaches you how to differentiate among the three states of matter. It also defines a physical property and lists examples of physical properties and physical changes. Describing Matter (pages 34 35) 1. What is matter? 2. The of an object is the amount of matter the object contains. 3. What is an extensive property? 4. What is an intensive property? 5. Matter that has a uniform and definite composition is called a. 6. How many kinds of matter does a pure substance contain? 7. Is the following sentence true or false? All samples of a substance have different physical properties. 8. A physical property is a quality or condition of a substance that can be or without changing the substance s composition. 9. Circle the letter of the term that is NOT a physical property. a. odor b. density c. boiling point d. corrosion 10. Is the following sentence true or false? A chemist can help identify a substance by its physical properties. States of Matter (pages 36 37) 11. Circle the letter of the term that is NOT a physical state of matter. a. water b. gas c. liquid d. solid

2 12. Match each arrangement of the particles in matter with a physical state. Physical State gas liquid solid Arrangement a. packed tightly together b. close, but not rigidly packed c. spaced far apart 13. Is the following sentence true or false? The words gas and vapor can be used interchangeably. 14. The term gas is limited to those substances that exist in the gaseous state at ordinary and. 15. What is vapor? Physical Changes (page 37) 16. A physical change alters a given material without changing its chemical. 17. What are some words that describe physical change? 18. What do boiling, melting and freezing have in common? SECTION 2.2 MIXTURES (pages 38 41) This section explains how to categorize a sample of matter as a substance or a mixture. It also teaches you how to distinguish between homogeneous and heterogeneous samples of matter. Classifying Mixtures (pages 38 39) 19. Is the following sentence true or false? Most samples of matter are mixtures. 20. What is a mixture? 21. Is the following sentence true or false? A heterogeneous mixture is one that has a completely uniform composition. 22. What is another name for a homogeneous mixture? 23. Circle the letter of the term that describes a part of a system with uniform composition and properties. a. solution b. mixture c. state d. phase 24. How many phases exist in these types of mixtures? a. Homogeneous b. Heterogeneous

3 Match each type of solution with an example of it. 25. solid-solid a. sugar water 26. solid-liquid b. carbon mixed with iron to form steel 27. gas-liquid c. soda water 28. gas-gas d. air Separating Mixtures (pages 40 41) 29. Is the following sentence true or false? It is always easy to separate the components in mixtures. SECTION 2.3 ELEMENTS AND COMPOUNDS (pages 42 47) This section explains the difference between an element and a compound. It also helps you identify the chemical symbols of common elements, and name common elements, given their symbols. Distinguishing Elements and Compounds (pages 42 43) 30. What are the two groups into which substances can be classified? and 31. Is the following sentence true or false? Elements can be separated easily into simpler substances. 32. Compounds are substances that can be separated into simpler substances only by means. 33. Is the following sentence true or false? The properties of compounds are different from those of their component elements. Distinguishing Substances and Mixtures (page 44) 34. Is the following sentence true or false? The elements that make-up a substance is always present in the same proportions. Symbols and Formulas (pages 45 47) 35. What is used to represent each element? 36. What are chemical symbols used for? 37. The subscript numbers in chemical formulas represent the proportions of the various elements in the. 38. Use the periodic table to answer the following questions. a. Pb is the symbol for what element? b. What is the symbol for gold? c. Stibium is the Latin name for which element?

4 SECTION 2.4 CHEMICAL REACTIONS (pages 48 50) This section helps you differentiate between physical and chemical changes in matter. It also teaches you how to apply the law of conservation of mass. Chemical Changes (page 48) 39. What happens in a chemical reaction? 40. What is a chemical property? 41. Is the following sentence true or false? Chemical properties are observed only when a substance undergoes a chemical change. 42. In chemical reactions, the starting substances are called and the substances formed are called. 43. Circle the letter of the term that best completes the sentence. A chemical change results in a change in chemical composition of the substances involved. a. sometimes b. rarely c. always d. never Recognizing Chemical Reactions (page 49) 44. What are some words that describe chemical change? 45. Which representation of a chemical reaction is correct? a. products reactants b. reactants products Conservation of Mass (page 50) 46. During a chemical reaction, the mass of products is always equal to the mass of. 47. The law of conservation of mass states that in any physical change or chemical reaction, mass is neither nor.

5 Chemical vs. Physical Properties, Elements, Compounds and Mixtures Name Period Unit 1 HW 2 Worksheet (Goals 1 6) 1. In your own words, differentiate between the following terms: Chemical Change and a Physical Change Chemical Property and Physical Property 2. Indicate whether the following are physical or chemical changes. a. Melting candle wax b. Tearing Mg ribbon c. Adding HCl to Mg d. Tearing Paper e. Grinding CuSO 4 f. Burning Paper g. Heating CuSO 4 h. Dissolving NaCl i. Mixing NaCl and Sand

6 3. Describe the difference between elements, compounds, and mixtures. Give an example of an element, which is then in a compound, which is also in a mixture. 4. Can a compound be broken down to smaller components (i.e. elements or smaller compounds) by physical means? Use an example to support your position. 5. Describe the difference between a homogenous mixture and a heterogeneous mixture. Provide an example of each and explain why they homogeneous or heterogeneous. 6. Discuss why physical properties are better to use to separate mixtures than chemical properties. Use an example to illustrate your point.

7 Qualitative vs. Quantitative, Accuracy vs. Precision Name Period Unit 1 HW 3 Worksheet (Goal 8) 1. Identify the following as quantitative or qualitative measurements. a. A flame is hot. b. A candle has a mass of 90 g. c. Wax is soft. d. A candle s height decreased 4.2 cm/hr. 2. Which of these synonyms or characteristics apply to the concept of accuracy? Which apply to the concept of precision? a. multiple measurements b. correct c. repeatable d. reproducible e. single measurement f. true value 3. Under which circumstances could a series of measurements of the same quantity be precise but not accurate? 4. Comment on the accuracy and precision of these basketball free-throw shooters. a. 99 of 100 shots are made. b. 99 of 100 shots hit the front of the rim and bounce off. c. 33 of 100 shots are made; rest miss. 5. A student estimated the volume of a liquid in a beaker as 200 ml. When she poured the liquid into a graduated cylinder, she measured the volume as 208 ml. What is the percent error of the estimated volume from the beaker, taking the measurement in the graduated cylinder as the accepted value?

8 Significant Figures Name Period Unit 1 HW 4 Worksheet (Goals 10 11) 1. How many significant figures are there in each of the following quantities? a. 20 miles b g c. 11 m d s e o C f. 404 people g. 8.9 x 10-2 kg h L i. 22,000 s 2. Round each of these measurements to three significant figures. a L b cg c m d o C e x 10 4 mm f ml 3. Write each of the rounded measurements in problem 2 in scientific notation. a. b. c. d. e. f. 4. Round off the following numbers to the number of significant figures indicated. a g (2 sig fig) b s (3 sig fig) c L (2 sig fig) d mm (1 sig fig) e ml (3 sig fig) f kg (1 sig fig) 5. Express the following calculations in the proper number of significant figures and units. a. 129 g / 29.2 cm 3 b m / 45.4 s 2 c m x m d. 60 cm x cm e mm x mm x mm 6. Express the following calculations in the proper number of significant figures and units. a. 22 g g g b cm cm c ml ml d g 4 g e K K K

9 7. Water with a mass of 35.4 g is added to an empty flask with a mass of g. The mass of the flask and the water is g after a rubber stopper is added. Express the mass of the stopper to the correct number of significant figures. 8. A student measures the mass of an object to be grams using an electronic balance. When placed in a graduated cylinder, the object displaced 9.9 ml of water. What is the density of the object? 9. What is the volume of a glass cylinder with an inside diameter of 6.0 cm and a height of 28 cm? (The volume of a cylinder equals pi x radius squared x height)

10 Metric Unit Conversions and Dimensional Analysis Name Period Unit 1 HW 5 Worksheet (Goals 12 14) 1 km = 1000 m 1 kg = 1000 g 1 L = 1000 ml Kelvin = o C m = 10 dm 1 g = 10 dg 1 ml = 1 cm cm 100 cg 1000 mm 1000 mg 1 x 10 6 µm 1 x 10 6 µg 1 x 10 9 nm 1 x 10 9 ng Convert the Following Units: 63 m km Show All of Your Work (Use Dimensional Analysis) m mm kg g 89 cm m 450 ml L 36 o C K 6.3 x 10 3 mg g L ml 423 K o C

11 1. List the SI base unit for each of these quantities. a. time b. length c. temperature d. mass 2. Which would melt first, germanium (m.p. 1,210 K) or gold (m.p. 1,064 o C)? 3. A quarter has a mass of about 5.65 g. Express this mass in milligrams, kilograms and micrograms. 4. Write the following numbers in scientific notation. a b. 25,004 d. 1,000,000 e c Which is larger? a. 1 centigram or 1 milligram b. 1 liter or 1 centiliter c. 1 calorie or 1 kilocalorie d. 1 millisecond or 1 centisecond e. 1 microliter or 1 milliliter f. 1 cubic millimeter or 1 cubic decimeter 6. Make the following conversions. a ml/min to microliters per second b g/cm 2 to milligrams per square millimeter c kg/l to grams per cubic centimeter 7. A tank measuring 28.6 cm by 73.0 mm by 0.72 m is filled with olive oil that has a mass of 1.38 x 10 4 g. What is the density of olive oil in kilograms per liter?