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SOLUTION MANUAL

Chapter 1. Chemistry in Our Lives Chapter 2. Chemistry and Measurements Chapter 3. Matter and Energy Chapter 4. Atoms and Elements Chapter 5. Electronic Structure of Atoms and Periodic Trends Chapter 6. Ionic and Molecular Compounds Chapter 7. Chemical Quantities Chapter 8. Chemical Reactions Chapter 9. Chemical Quantities in Reactions Chapter 10. Bonding and Properties of Solids and Liquids Chapter 11. Gases Chapter 12. Solutions Chapter 13. Reaction Rates and Chemical Equilibrium Chapter 14. Acids and Bases Chapter 15. Oxidation and Reduction Chapter 16. Nuclear Chemistry Chapter 17. Organic Chemistry Chapter 18. Biochemistry

1 Chemistry in Our Lives Learning Goals • • • •

Define the term chemistry, and identify chemicals. Describe the scientific method. Identify strategies that are effective for learning. Develop a study plan for learning chemistry. Review math concepts used in chemistry: place values, positive and negative numbers, percentages, solving equations, and interpreting graphs. • Write a number in scientific notation.

Chapter Outline Chapter Opener: Forensic Scientist Chemistry and Chemicals Scientific Method: Thinking Like a Scientist Chemistry Link to Health: Early Chemist: Paracelsus Studying and Learning Chemistry Key Math Skills for Chemistry Writing Numbers in Scientific Notation Update: Forensic Evidence Helps Solve the Crime

1.1 1.2 1.3 1.4 1.5

Key Math Skills • • • • • •

Identifying Place Values (1.4) Using Positive and Negative Numbers in Calculations (1.4) Calculating Percentages (1.4) Solving Equations (1.4) Interpreting Graphs (1.4) Writing Numbers in Scientific Notation (1.5)

Answers and Solutions to Text Problems 1.1

a. Chemistry is the study of the composition, structure, properties, and reactions of matter. b. A chemical is a substance that has the same composition and properties wherever it is found.

1.2

Your friends may give a variety of answers, most of which will probably not agree with the definitions you provided.

1.3

Many chemicals are listed on a bottle of multivitamins such as vitamin A, vitamin B3, vitamin B12, vitamin C, and folic acid.

1.4

Many chemicals are listed on a cereal box such as vitamin A, vitamin B6, vitamin B12, vitamin C, folic acid, sugar, salt, and iron.

Chapter 1

1.5

Typical items found in a drugstore and some of the chemicals they contain are as follows: Antacid tablets: calcium carbonate, cellulose, starch, stearic acid, and silicon dioxide Mouthwash: water, alcohol, thymol, glycerol, sodium benzoate, and benzoic acid Cough suppressant: menthol, beta-carotene, sucrose, and glucose

1.6

Typical chemicals found in dishwashing products are: water, sodium lauryl sulfate, sodium laureth sulfate, dimethyl amine oxide, sodium chloride, and phenoxyethanol.

1.7

a. observation d. observation

b. hypothesis e. observation

c. experiment f. conclusion

1.8

a. observation d. experiment

b. hypothesis e. observation

c. experiment f. hypothesis

1.9

a. observation

b. hypothesis

c. experiment

d. experiment

1.10 a. hypothesis

b. observation

c. experiment

d. conclusion

1.11 There are several things you can do that will help you successfully learn chemistry, including attending class regularly, forming a study group, reading the assigned pages in the textbook before class, answering the Engage questions as you read new material in the textbook, trying to solve the Sample Problems first before reading the provided Solutions, working the Self Tests and Practice Problems and checking the Answers, self-testing during and after r eading each section, retesting on new information a few days later, going to the instructor’s office hours, and keeping a problem notebook. 1.12 Many things make it difficult to learn chemistry, including not going to class regularly, not working Sample Problems and Self Tests, not reading the assignment ahead of class, not going to the instructor’s office hours, and waiting until the night before an exam to study. 1.13 Ways you can enhance your learning of chemistry include a. forming a study group. c. asking yourself questions while reading the text. e. answering the Engage questions. 1.14 Ways you can enhance your learning of chemistry include a. studying different topics at the same time. c. attending review sessions. d. working the problems again after a few days. e. keeping a problem notebook. 1.15 a. The bolded 8 is in the thousandths place. c. The bolded 2 is in the tenths place. e. The bolded 9 is in the hundredths place.

b. The bolded 6 is in the ones place. d. The bolded 6 is in the hundreds place.

1.16 a. The bolded 9 is in the hundreds place. c. The bolded 6 is in the ones place. e. The bolded 1 is in the hundredths place.

b. The bolded 7 is in the tens place. d. The bolded 8 is in the tenths place.

1.17 a. 15 - (-8) = 15 + 8 = 23 c. 4 * (-2) + 6 = -8 + 6 = -2

b. -8 + (-22) = -30 d. 75 - (-44) - 65 = 75 + 44 - 65 = 54

-25 + (-11) -36 = = -12 -3 + 6 3

b. 34 + (-55) = -21 1.18 a. -11 - (-9) = -11 + 9 = -2 -56 = -7 c. d. 0.04 + (-0.08) = -0.04 8 -2 * (-4) 8 e. + 12 = + 12 = 4 + 12 = 16 2 2

Chemistry in Our Lives

4a + 4 = 40 1.19 a. 4a + 4 - 4 = 40 - 4 4a = 36 4a 36 = 4 4 a = 9 c.

a = 7 6

a 6 a b = 6(7) 6 a = 42

55 - a + 15 = a 4 55 - a + 15 4a b = 4(a) 4

6a - 27 = -3a 6a - 27 + 27 = -3a + 27 6a = -3a + 27 6a + 3a = -3a + 27 + 3a 9a = 27 9a 27 = 9 9 a = 3

55 - a + 15 = 4a 70 - a = 4a 70 - a + a = 4a + a 70 = 5a 70 5a = 5 5 a = 14

1.20 a. 2b + 7 = b + 10 2b + 7 - 7 = b + 10 - 7 2b = b + 3 2b - b = b - b + 3 b = 3

-16 - 2b + 8b c. = b 2 -16 - 2b + 8b 2a b = 2(b) 2 -16 - 2b + 8b = 2b -16 + 6b = 2b -16 + 16 + 6b = 2b + 16 6b = 2b + 16 6b - 2b = 2b + 16 - 2b 4b = 16 4b 16 = 4 4 b = 4

6a - 27 = -a 3 6a - 27 3a b = 3(-a) 3

3b - 4 = 24 - b 3b - 4 + 4 = 24 - b + 4 3b = 28 - b 3b + b = 28 - b + b 4b = 28 4b 28 = 4 4 b = 7 3 * (-4b) + 32 = -4b 2 3 * (-4b) + 32 2a b = 2(-4b) 2 3 * (-4b) + 32 = 2(-4b) -12b + 32 = -8b -12b + 32 + 12b = -8b + 12b 32 = 4b 32 4b = 4 4 b = 8

1.21 a. The graph shows the relationship between the temperature of a cup of tea and time. b. The vertical axis measures temperature, in °C. c. The values on the vertical axis range from 20 °C to 90 °C. d. As time increases, the temperature decreases. 1.22 a. The horizontal axis measures time, in minutes. b. The values on the horizontal axis range from 0 min to 100 min. c. After 20 min, the temperature of the tea is about 56 °C. d. About 38 min were required for the tea to reach a temperature of 45 °C. Copyright © 2020 Pearson Education, Inc.

Chapter 1

21 flu shots * 100, = 84, received flu shots 25 patients b. total grams of alloy = 56 g silver + 22 g copper = 78 g of alloy 56 g silver * 100, = 72, silver 78 g alloy c. total number of coins = 11 nickels + 5 quarters + 7 dimes = 23 coins 7 dimes * 100, = 30, dimes 23 coins 2.2 g sodium chloride d. * 100, = 5, sodium chloride 44 g saline solution 1.23 a.

22 boys * 100, = 63, boys 35 babies b. total grams of alloy = 67 g gold + 35 g zinc = 102 g of alloy

1.24 a.

35 g zinc * 100, = 34, zinc 102 g alloy c. total number of coins = 15 pennies + 14 dimes + 6 quarters = 35 coins 15 pennies * 100, = 43, pennies 35 coins 18 dextrose IV bags d. * 100, = 32, dextrose IV bags 56 IV bags 1.25 a. The graph shows the relationship between body temperature and time since death. b. The vertical axis measures temperature, in °C. c. The values on the vertical axis range from 20 °C to 44 °C. d. As time increases, the temperature decreases. 1.26 a. The horizontal axis measures time, in hours, since death. b. The values on the horizontal axis range from 0 h to 25 h. c. About 15 hours were needed to reach a body temperature of 28 °C. d. Since it takes about 5 hours to reach a body temperature of 34 °C, the time of death is estimated to be (9 p.m. – 5 h =) 4 p.m. 1.27 a. Move the decimal point four places to the left to give 5.5 * 104. b. Move the decimal point two places to the left to give 4.8 * 102. c. Move the decimal point six places to the right to give 5 * 10-6. d. Move the decimal point four places to the right to give 1.4 * 10-4. e. Move the decimal point three places to the right to give 7.2 * 10-3. f. Move the decimal point five places to the left to give 6.7 * 105. 1.28 a. Move the decimal point eight places to the left to give 1.8 * 108. b. Move the decimal point five places to the right to give 6 * 10-5. c. Move the decimal point two places to the left to give 7.5 * 102. d. Move the decimal point one place to the right to give 1.5 * 10-1. e. Move the decimal point two places to the right to give 2.4 * 10-2. f. Move the decimal point three places to the left to give 1.5 * 103. 1.29 a. The standard number is 1.2 times the power of 104 or 10 000, which gives 12 000. b. The standard number is 8.25 times the power of 10-2 or 0.01, which gives 0.0825. c. The standard number is 4 times the power of 106 or 1 000 000, which gives 4 000 000. d. The standard number is 5.8 times the power of 10-3 or 0.001, which gives 0.0058.

Chemistry in Our Lives

1.30 a. The standard number is 3.6 times the power of 10-5 or 0.000 01, which gives 0.000 036. b. The standard number is 8.75 times the power of 104 or 10 000, which gives 87 500. c. The standard number is 3 times the power of 10-2 or 0.01, which gives 0.03. d. The standard number is 2.12 times the power of 105 or 100 000, which gives 212 000. 1.31 a. hypothesis

b. conclusion

c. experiment

d. observation

1.32 a. hypothesis

b. experiment

c. observation

d. conclusion

1.33

120 g ethylene glycol * 100, = 27, ethylene glycol 450 g liquid

1.34

1.5 g ethylene glycol * 100, = 0.15, ethylene glycol 1000 g body mass

1.35 No. All of these ingredients are chemicals. 1.36 No. All of these ingredients are chemicals. 1.37 Yes. Sherlock’s investigation includes making observations (gathering data), formulating a hypothesis, testing the hypothesis, and modifying it until one of the hypotheses is validated. 1.38 Holmes stresses the important first step of the scientific method: making observations and collecting data. 1.39 a. When two negative numbers are added, the answer has a negative sign. b. When a positive and negative number are multiplied, the answer has a negative sign. 1.40 a. When a negative number is subtracted from a positive number, the answer has a positive sign. b. When two negative numbers are divided, the answer has a positive sign. 1.41 a. observation

b. hypothesis

c. observation

1.42 a. observation

b. observation

c. hypothesis

1.43 If experimental results do not support your hypothesis, you should b. modify your hypothesis. c. do more experiments. 1.44 A hypothesis is supported when b. many experiments validate the hypothesis. 1.45 a. observation

b. hypothesis

c. conclusion

1.46 a. observation

b. hypothesis

c. experiment

1.47 A successful study plan would include b. working the Sample Problems as you go through a chapter. c. self-testing. e. reading the assignment before class. 1.48 A successful study plan would include c. working problems in a notebook for easy reference. d. forming a study group and discussing the problems together. e. reviewing Key Math Skills and Core Chemistry Skills. 1.49 a. 4 * (-8) = -32 b. -12 - 48 = -12 + (-48) = -60 -168 c. = 42 -4

Chapter 1

1.50 a. -95 - (-11) = -95 + 11 = -84 152 = -8 -19 c. 4 - 56 = 4 + (-56) = -52 b.

1.51 total number of gumdrops = 16 orange + 8 yellow + 16 black = 40 gumdrops 8 yellow gumdrops * 100, = 20, yellow gumdrops a. 40 total gumdrops 16 black gumdrops b. * 100, = 40, black gumdrops 40 total gumdrops 1.52 total number of students = 12 As + 18 Bs + 20 Cs = 50 students 18 Bs a. * 100, = 36, Bs 50 total students 20 Cs * 100, = 40, Cs b. 50 total students 1.53 a. Move the decimal point five places to the left to give 1.2 * 105. b. Move the decimal point seven places to the right to give 3.4 * 10-7. c. Move the decimal point two places to the right to give 6.6 * 10-2. d. Move the decimal point three places to the left to give 2.7 * 103. 1.54 a. Move the decimal point three places to the right to give 4.2 * 10-3. b. Move the decimal point two places to the left to give 3.1 * 102. c. Move the decimal point eight places to the left to give 8.9 * 108. d. Move the decimal point eight places to the right to give 5.6 * 10-8. 1.55 a. Move the decimal point five places to the left to give 0.000 026. b. Move the decimal point two places to the right to give 650. c. Move the decimal point one place to the left to give 0.37. d. Move the decimal point five places to the right to give 530 000. 1.56 a. Move the decimal point two places to the left to give 0.072. b. Move the decimal point three places to the right to give 1440. c. Move the decimal point four places to the left to give 0.000 48. d. Move the decimal point six places to the right to give 9 100 000. 1.57 a. observation

b. hypothesis

c. conclusion

1.58 a. observation

b. experiment

c. conclusion

1.59 a. observation

b. hypothesis

c. experiment

d. conclusion

1.60 a. observation

b. hypothesis

c. observation

d. observation

1.61 a. 2x + 5 = 41 2x + 5 - 5 = 41 - 5 2x = 36 2x 36 = 2 2 x = 18

5x = 40 3 5x 3 a b = 3(40) 3 5x = 120 5x 120 = 5 5 x = 24 b.

Chemistry in Our Lives

1.62 a. 3z - (-6) = 12 3z + 6 = 12 3z + 6 - 6 = 12 - 6 3z = 6 3z 6 = 3 3 z = 2

4z = -8 -12 4z -12 a b = -12(-8) -12 4z = 96 4z 96 = 4 4 z = 24 b.

1.63 a. The graph shows the relationship between the solubility of carbon dioxide in water and temperature. b. The vertical axis measures the solubility of carbon dioxide in water (g CO2/100 g water). c. The values on the vertical axis range from 0 to 0.35 g CO2/100 g water. d. As temperature increases, the solubility of carbon dioxide in water decreases. 1.64 a. The horizontal axis measures temperature, in °C. b. The values on the horizontal axis range from 0 °C to 60 °C. c. At 25 °C, the solubility of carbon dioxide in water is about 0.17 g CO2/100 g water. d. Carbon dioxide has a solubility of 0.20 g CO2/100 g water at a temperature of about 16 °C.

Answers to Combining Ideas from Chapters 1 to 3 CI.1 a. There are 4 significant figures in the measurement 20.17 lb. 1 kg b. 20.17 lb * = 9.147 kg (4 SFs) 2.205 lb 1000 g 1 cm3 c. 9.147 kg * * = 474 cm3 (3 SFs) 1 kg 19.3 g d. TF = 1.8(TC) + 32 = 1.8(1064) + 32 = 1947 °F (4 SFs) TK = TC + 273 = 1064 + 273 = 1337 K (4 SFs) e. ∆T = 1064 °C - 500. °C = 564 °C 1000 g 0.129 J 1 cal 1 kcal 9.147 kg * * * * 564 °C * = 159 kcal (3 SFs) 1 kg g °C 4.184 J 1000 cal 1000 g +42.06 f. 9.147 kg * * = +384 700 (4 SFs) 1 kg 1g 1 gal 35 mi 1 km * * = 330 km (2 SFs) 3.785 L 1 gal 0.6214 mi 1 gal +2.82 b. 22 L * * = +16 (2 SFs) 3.785 L 1 gal 1 gal 35 mi 1h c. 22 L * * * = 4.6 h (2 SFs) 3.785 L 1 gal 44 mi 0.74 g 1000 mL d. 22 L * * = 16 000 g (2 SFs) 1L 1 mL 0.74 g 1000 mL 47 kJ e. 22 L * * * = 7.7 * 105 kJ (2 SFs) 1L 1 mL 1g

CI.2 a. 22 L *

CI.3 a. The water has its own shape in sample B. b. Water sample A is represented by diagram 2, which shows the particles in a random arrangement but close together. c. Water sample B is represented by diagram 1, which shows the particles fixed in a definite arrangement. d. The state of matter indicated in diagram 1 is a solid; in diagram 2, it is a liquid; and in diagram 3, it is a gas. e. The motion of the particles is slowest in diagram 1. f. The arrangement of particles is farthest apart in diagram 3. g. The particles fill the volume of the container in diagram 3. CI.4 a. Food Type

Carbohydrate Fat Protein

Mass

4 kcal 1g 9 kcal 5g * 1g 4 kcal 10. g * 1g Total energy content 39 g

Energy (rounded off to the tens place)

Energy Value

160 kcal

50 kcal

40 kcal

250 kcal

Answers to Combining Ideas from Chapters 1 to 3

b. Food Type

Carbohydrate Fat Protein

Mass

17 kJ 1g 38 kJ 5g * 1g 17 kJ 10. g * 1g Total energy content 39 g

Energy (rounded off to the tens place)

Energy Value

660 kJ

190 kJ

170 kJ

1020 kJ

68 g bar = 11 g of energy bar (2 SFs) 1020 kJ 1020 kJ 1h 60 min * * = 150 min (2 SFs) d. 2 bars * 1 bar 840 kJ 1h

c. 160 kJ *

453.6 g 1 cm3 * = 14.4 cm3 (3 SFs) 1 lb 7.86 g 14.4 cm3 b. 30 nails * = 5.76 cm3 = 5.76 mL (3 SFs) 75 nails New water level = 17.6 mL water + 5.76 mL = 23.4 mL (3 SFs)

CI.5 a. 0.250 lb *

c. ∆T = 125 °C - 16 °C = 109 °C Heat = m * ∆T * SH 453.6 g 0.452 J = 0.250 lb * * 109 °C * = 5590 J (3 SFs) 1 lb g °C CI.6 a. 450 gal *

3.785 L = 1700 L (2 SFs) 1 gal

1.00 g 1 kg 3.785 L 1000 mL * * * = 1700 kg (2 SFs) 1 gal 1L 1 mL 1000 g c. Convert temperatures to Celsius: (105 - 32) TF - 32 73 TC = = = = 41 °C 1.8 1.8 1.8 (62 - 32) TF - 32 30. TC = = = = 17 °C 1.8 1.8 1.8 ∆T = 41 °C - 17 °C = 24 °C 1000 g 1.00 cal 1 kcal Heat = m * ∆T * SH = 1700 kg * * 24 °C * * 1 kg g °C 1000 cal = 41 000 kcal (2 SFs) b. 450 gal *

d. ∆T = 41 °C - 17 °C = 24 °C (as in part c solution) 1000 g 4.184 J 1 kJ 1 min 1700 kg * * 24 °C * * * = 29 min (2 SFs) 1 kg g °C 1000 J 5900 kJ