Answers to In-Chapter Practice Problems

Chemistry Skill Handbook Supplemental Practice Problems Safety Handbook Chemistry Data Handbook Answers to In-Chapter Practice Problems... 

Each Example includes a stategy that describes how to approach the problem. After describing the solution, we offer an Extra Practice Exercise designed to help you master the particular type of problem while the example is fresh in your mind. The answers to these Extra Practice Exercises appear at the end of each chapter, along with the answers to the Section Exercises. 

Each Example is accompanied by an Exercise, which is a similar problem that you can try. The answers to these Exercises are at the end of the book. At the end of each Exercise is a hst of corresponding end-of-chapter Practice Problems. Try some of these to gain mastery of that problem-solving skill. Problems are in matched pairs, and answers to odd-numbered Problems are provided at the end of the book. 

Two Practice Examples are provided for each worked-out Example. The first. Practice Example A, provides immediate practice in a problem very similar to the given Example. The second. Practice Example B, often takes the student one step further than the given Example and is similar to the end-of-chapter problems in terms of level of difficulty. Answers to all the Practice Examples are given in Appendix G. 

We have introduced into each chapter a number of worked examples which we believe are essential to a proper understanding of the methods of treatment given in the text. It is very desirable for a student to understand a worked example before tackling fresh practical problems himself. Chemical Engineering problems require a numerical answer, and it is essential to become familiar with the different techniques so that the answer is obtained by systematic methods rather than by intuition. ... 

In this concluding Chapter the problems identified from practice and literature and the research questions derived from these observations will be reviewed. Subsequently, the results from the previous Chapters will be used to obtain the answers to these research questions. Moreover, a reflection on the results and answers will be stated. Finally, some opportunities for future research will be presented. 

In this section, we will introduce one of the two common methods for solving problems. (You will see the other method in Chapter 5.) This is the Unit Conversion Method. It will be very important for you to take time to make sure you fully understand this method. You may need to review this section from time to time. The Unit Conversion Method, sometimes called the Factor-Label Method or Dimensional Analysis, is a method for simplifying chemistry problems. This method uses units to help you solve the problem. While slow initially, with practice it will become much faster and second nature to you. If you use this method correctly, it is nearly impossible to get the wrong answer. For practice, you should apply this method as often as possible, even though there may be alternatives. 

Here are the answers and explanations to the chapter quiz. Read them over carefully for explanations of any problems that you answered incorrecdy. For more information and practice on the properties of numbers, see LearningExpress s Practical Math Success in 20 Minutes a Day, Lesson 20. 

If you answered 1-3 questions correctly, give the lessons in this chapter your full concentration. Read carefully through all explanations. Try all examples on your own. Visit the suggested websites and work through any problems given. You may need to reference a suggested book that will present the material in an alternate form. After reviewing the lessons, retry the benchmark questions and then proceed to the practice problems. 

The final chapter to review is math word problems. Word problems cover any of the topics in previous chapters. Word problems are daunting for many people. Follow the suggestions in this chapter to meet this math challenge and score high on your test. Before you begin, spend a few minutes to take this ten-question Benchmark Quiz. These questions are similar to the type of questions that you will find on important tests. When you are finished, check the answer key carefully to assess your results. Your Benchmark Quiz analysis will help you determine how much time you need to spend on word problems and the specific areas in which you need the most careful review and practice. 

If you answered 1-3 questions correctly, you need to make a concentrated effort to practice word problems. Perhaps you become intimidated as soon as you encounter words in a math problem. Read this chapter carefully. There are many suggestions and approaches described to make solving word problems simpler. Practice is the key to success. Pay attention to all tips, rules, and shortcuts and visit the suggested websites for further practice. You may want to refer to Practical Math Success in 2 0 Minutes a Day, published by LearningExpress, which has two Lessons, 15 and 16, devoted to word problems. 

We have in this chapter emphasized the practical advantage of a problem-centered approach in which a problem is selected for study in the light of individuality. An application of this approach would cause one to ask such questions as these What have somatotypes to do with ulcers What have they to do with diabetes mellitus What have they to do with sex functions The answers to these questions, since somatotyping is on a standardized and systematic basis, should be definite and conclusive. These pointed single questions might well be substituted, in our opinion, for the more general question which... 

The following are the answers to the practice problems in this chapter. 

Now that you ve organized the facts on atoms into clearly labeled compartments in your brain, see how accessible that information is. Check your answers to the practice problems presented in this chapter. 

Here are the answers to the practice problems in this chapter. Pat yourself on the back, whether in congratulation or consolation. 

Are you charged up to check your answers Take a gander at this section to see how you did on the practice problems in this chapter. 

This text is aimed at a nonexpert audience and designed as a tutorial material for teachers and students who would like to teach and use VB theory, but who otherwise have basic knowledge of quantum chemistry. As such, the primary focus of this textbook is a qualitative insight of the theory and ways to apply this theory to the problems of bonding and reactivity in the ground and excited states of molecules. Almost every chapter contains problem sets followed by answers. These problems provide the teachers, students, and interested readers with an opportunity to practice the art of VB theory. We will be indebted to readers—teachers—students for comments and more suggestions, which can be incorporated into subsequent editions of this book that we hope, will follow. 

Many practical problems in heat transfer are solved with computer techniques. In the chapters which follow, many examples will be presented to illustrate setups for computer solutions, and many end-of-chapter problems will pose interesting questions to be answered by the reader. But this is not to play down analysis or appreciation of the fundamental principles of the subject. These principles are even more important in computer work because the engineer must be extra careful about input variables and have a notion of the correct magnitude of the output from the computer. 

After most numbered examples, a practice problem is presented for the students to practice the problem-solving method. The complete answers are presented in Appendix 4. The smdents will then use these methods to solve the end-of-chapter problems. 

Note that it may be surprising that a chemical term is considered in Eq. (3), whereas we have supposed that no chemical reaction term was involved within the stagnant layer. As explained in Chapter 1, this stems from the fact that the effect of any chemical reaction within the diffusion layer depends on the relative magnitude of k5 /D versus unity. For usual laboratory conditions, 8 10 cm and D 5 x IC cm s and then 5 /D is of the order of 0.2 s. Thus, provided k is less than approximately 1 s it has no tangible effect on the concentration profiles of the species, whereas it has a definite effect in the bulk solution due to the long reaction times (usually longer or comparable to half an hour). In practice it is important to decide when the simplification in Eq. (2) or (3) applies to a given experimental situation. The discussion just presented affords a simple answer to the problem. Indeed, consider the electron transfer reaction in Eq. (5), possibly followed by a chemical step in Eq. (6). 

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