Chemistry: Principles and Reactions, 7 edition

Book Preface

When a professor is asked what a preface is, she might paraphrase Webster’s dictionarythus:

A preface is an essay found at the beginning of a book. It is written by the author to set the book’s purpose and sometimes to acknowledge the assistance of others.

A ni eteen-year-old college freshman, when asked what a preface is, could tell youthat
it was the debut album (released in August 2008) of hip-hop rapper eLZhi. This  difference in mindset is the impetus for this edition.

We recognize that today’s freshmen are quite different from those of a few years ago. Text messaging and twitterTM have strongly influenced sentence length and structure. In current writing and conversation, short sentences or sentence fragments convey straightto- the-point information. Multimedia presentations are a way of life. Reflecting all this, we have come up with a seventh edition written by a “revised” team. The new member (EJN) is young enough to be fully in tune with today’s technology and speech.

Are We Still Committed to Writing a Short Book?

The answer is an emphatic yes! Rising tuition costs, depleted forests, and students’ aching backs have kept us steadfast in our belief that it should be possible to cover a text completely (or at least almost completely) in a two-semester course. The students (and their parents) justifiably do not want to pay for 1000-page books with material that is never discussed in the courses taught with those texts.

What Is Our Criterion for Writing a Short Book?

The common perception is that a short book is a low-level book. We believe, however, that treating general concepts in a concise way can be done without sacrificing depth, rigor, or clarity. Our criterion for including material continues to be its importance and relevance to the student, not its difficulty. To achieve this, we decided on the following guidelines.

1. Eliminate repetition and duplication wherever possible. Like its earlier editions, this text uses
• Only one method for balancing redox reactions, the half-equation method introduced in Chapter 4.
• Only one way of working gas-law problems, using the ideal gas law in all cases (Chapter 5).
• Only one way of calculating ΔH (Chapter 8), using enthalpies of formation.
• Only one equilibrium constant for gas-phase reactions (Chapter 12), the thermodynamic constant K, often referred to as Kp. This simplifies not only the treatment of gaseous equilibrium but also the discussion of reaction spontaneity (Chapter 16) and electrochemistry (Chapter 17).

2. Relegate to the Appendices or Beyond the Classroom essays topics ordinarily covered in longer texts. Items in this category include
• MO (molecular orbital) theory (Appendix 4). Our experience has been (and continues to be) that although this approach is important to chemical bonding, most general chemistry students do not understand it but only memorize the principles discussed in the classroom.
• Nomenclature of organic compounds. We believe that this material is of little value in a beginning course and is better left to a course in organic chemistry.
• Qualitative analysis. This is summarized in a few pages in an essay in Chapter 15 in the Beyond the Classroom section. An extended discussion of the qualitative scheme and the chemistry behind it belongs in a laboratory manual, not a textbook

• Biochemistry. This material is traditionally covered in the last chapter of general chemistry texts. Although we have included several biochemical topics in the text (among them a discussion of heme in Chapter 19 and carotenoids in Chapter 6), we do not see the value of an entire chapter on biochemistry. Interesting as this material is, it requires a background in organic chemistry that first-year students lack.

3. Avoid superfluous asides, applications to the real world, or stories about scientists in the exposition of principles. We have incorporated many applications in the context of problems and some of the exposition of general principles. In general, however, we have stayed with a bare-bones approach. Students can easily be distracted by interesting but peripheral tidbits while they are striving hard to understand the core concepts. We have put some of our favorite real-world applications and personal stories about scientists in separate sections, Beyond the Classroom and Chemistry: The Human Side. Our students tell us that they read these two sections first and that these are the parts of the book that “we really enjoy the most.” (Talk about faint praise!) They do admit to enjoying the marginal notes too.