INTRODUCTION TO CHEMIST RY AND INTRODUCTIO N TO ACTIVE LEARNING

1.1

CHAPTER 1

INTRODUCTION TO CHEMIST RY AND INTRODUCTIO N TO ACTIVE LEARNING

Authors’ Comments on Chapter 1

Chapter 1 has three parts. The first part, entitled Introduction to Chemistry, is an introduction to the scientific method and the science of chemistry.The second part, entitled Introduction to Active Learning, is a discussion of how to study for a chemistry course and an overview of the learning tools in the textbook. Section 1.4, Learning How to Learn Chemistry, emphasizes the importance of making good academic choices that will lead to success in challenging courses such as introductory chemistry. Section 1.5, Your Textbook, introduces students to the array of learning tools presented in the textbook. Since our book contains many one-of-a-kind features, it is important for students to spend a few minutes at the beginning of the course learning how the book is uniquely designed to help them learn chemistry.The third part, entitled A Choice, Section 1.6, is simply three paragraphs that emphasize that one must choose to be disciplined when in a course that requires an investment of study time outside of class.Chapter 1 is optional and can be omitted without loss of continuity, but we recommend that it be assigned in its entirety. Since the chapter is only 16 pages long and free of abstract scientific concepts, it can be studied independently in a reasonably short amount of time. If you want to spend the first day of class introducing the scientific method, the textbook, and your syllabus—the presentation slides give you a framework for doing so—then the study of Chapter 1 can be the first homework assignment. You may want to have students turn in their study plan and weekly calendar (Questions, Exercises, and Problems) at the second class meeting.Answers Only for Black-Numbered Unanswered Questions, Exercises, and Problems Chapter 1 has no Questions, Exercises, and Problems that have “correct answers.” Introductory Chemistry, An Active Learning Approach, 7e Mark Cracolice, Edward Peters (Instructor Manual, All Chapters. 100% Original Verified, A+ Grade)

• / 4

Instructor’s Manual for Cracolice/Peters Introductory Chemistry: An Active Learning Approach, 7th Edition 1.2 Solutions for Black-Numbered Unanswered Questions, Exercises, and Problems The two questions in Chapter 1 are designed to help set up for success students who have little or no experience with college science courses. We find that many new college students were successful in their high school science courses by studying outside of class only on the evenings before exam days. They enter college with the expectation that they are going to be in “13th grade,” where the continuation of their high school study “strategy” will be sufficient. As we point out in Section 1.4, failure to commit sufficient time outside of class is the biggest problem when it comes to learning chemistry. Developing a study plan and a weekly calendar should help students to ensure that they are making an appropriate commitment to doing homework. 2 / 4

Instructor’s Manual for Cracolice/Peters Introductory Chemistry: An Active Learning Approach, 7th Edition 2.1

CHAPTER 2

MATTER AND ENERGY

Authors’ Comments on Chapter 2 Chapters 2 and 3 are interchangeable. Chapter 2 is an introduction to matter and energy. Chapter 3 is an introduction to measurement and problem-solving. We sequenced the chapters in this order so that the introduction to measurement and problem-solving can be immediately followed by a chapter where students have to apply these newly learned skills. Chapter 4 is an introduction to gases. It allows students to solve problems and learn how gas measurements are made. Another reason for sequencing matter and energy before measurement and problem-solving is that we prefer to start our courses with some “chemistry,” as presented in Chapter 2, rather than “math,” as presented in Chapter 3.

Answers for Everyday Chemistry Quick Quiz Questions

• A DNA fingerprint is an x-ray of radioactive probes that are attached to DNA fragments.
• Some advantages include: Criminals can avoid leaving fingerprints at a crime scene; DNA can be

extracted from many sources other than fingertips, such as hair, blood, sweat, and saliva; only a small sample of biological material is needed; DNA fingerprinting can be used to identify nonhuman animals and other organisms.

Answers Only for Black-Numbered Unanswered Questions, Exercises, and Problems

• Macroscopic: c. Microscopic: a. Particulate: b.
• Chemists use models, real or imaginary or both, to represent the invisible particles that make up matter.
• Ice consists of water molecules that vibrate or shake in fixed positions relative to one another. Ice has a

fixed shape. When ice melts, the molecules remain together but move freely among each other at the bottom of the container that holds them, assuming the shape of the container. As a gas, the molecules separate, moving freely throughout a closed container or escaping into the atmosphere from an open container. 3 / 4

Instructor’s Manual for Cracolice/Peters Introductory Chemistry: An Active Learning Approach, 7th Edition 2.2

• The particles in a solid occupy fixed positions relative to each other and cannot be poured, but different

pieces of solids can move relative to each other. The slogan emphasizes that this brand of table salt has solid pieces small enough to move freely relative to one another, but not so small that they stick together in humid weather.

• Liquid volume is usually slightly greater than solid; gas volume is very much larger than liquid.
• Chemical: a. Physical: b, c.
• Chemical: a, b. Physical: c.
• The change is chemical because the diatomic reactant molecules are destroyed, changing to monatomic

atoms.

• If both products are the same pure substance, they must be identical; thus, purchasing the new, half-

priced product is the better choice.

• The photograph alone does not provide enough information to answer the question. You probably

know, however, that dishwashing liquid is a mixture.

• All are mixtures.
• (a) is a mixture because different substances are visible. (b) could be a pure substance in two different

states, but it is probably a mixture. (c) could be either a pure substance or a mixture because it may be one kind of matter or two or more types of matter with similar appearances.

• Yes—the terms homogeneous and heterogeneous refer to the macroscopic appearance and composition

of a sample. A container filled with ice and liquid water is heterogeneous in appearance but is also pure, as long as in both phases the water is pure.

• Homogeneous: a, c. Heterogeneous: b.
• The cylinder appears the same throughout, and it can be assumed that the percentage of each element is

constant, so it is a homogeneous substance.

• Your sketch should include two or more different types of particles mixed together (a mixture), evenly

distributed in the same phase of matter (so that it will appear homogeneous).

• Pick out table tennis balls or ball bearings based on size and appearance; use magnetic properties of

steel to pick up ball bearings with a magnet; use the lower density of balls and higher density of steel to float the balls in water. These methods are based on physical properties.

• / 4