Student spreadsheet

Overall, our impressions of the exercise have been positive. Students have produced some extraordinary spreadsheets, often making use of features of Excel that we had not previously been aware of, and the majority of students increased their understanding of the capabilities of Excel even if individually they may have taken little part in the group work. Over the years of running this exercise, there have been numerous examples of students reporting the value of this Excel exercise during subsequent vacation work experience, and of how employers have valued the students spreadsheet skills, in some cases even when students had failed the spreadsheet part of the assignment. 

Many of the topics covered in analytical chemistry benefit from the availability of appropriate computer software. In preparing this text, however, I made a conscious decision to avoid a presentation tied to a single computer platform or software package. Students and faculty are increasingly experienced in the use of computers, spreadsheets, and data analysis software their use is, I think, best left to the personal choice of each student and instructor. 

Using a spreadsheet function or analysis tool, perform a Smdent s f-test to compare the mean values of each of the first four wear rates with that of gold (the last value in the column) at an agreed-upon confidence level—for example, 95% confidence level. If you have not yet learned how to do Student s f-test, check out any book on elementary statistics, and learn how to do a f-test, or use the Help menus in your spreadsheet package. The goal is to determine if the mean wear rates of the four ceramic materials are statistically different from the wear rate for gold. If done correctly, you will have performed four separate f-tests in this step. 

Lim, K. F. "Using spreadsheets to teach quantum theory to students with weak calculus backgrounds," http //www.mathcentre.ac.uk/resources/ casestudies/mathsteam/lim.pdf, (Accessed May 22, 2006). 

Excel has built-in procedures for conducting tests with Student s t. To compare Rayleigh s two sets of results in Table 4-3, enter his data in columns B and C of a spreadsheet (Figure 4-8). In rows 13 and 14. we computed the averages and standard deviations, but we did not need to do this. 

The Student Web Site, www.whfreeman.com/cica7e, has directions for experiments that may be reproduced for your use. At this Web site, you will also find lists of experiments from the Journal of Chemical Education, a few downloadable Excel spreadsheets, and a few Living Graph Java applets that allow students to manipulate graphs by altering data points and variables. Supplementary topics at the Web site include spreadsheets for precipitation titrations, microequilibrium constants, spreadsheets for redox titration curves, and analysis of variance. 

Challenging Exercises Ken Whitmire of Rice University has compiled the end-of-chapter exercises from our own supply and has added new ones of his own. He has provided exercises that range from the straightforward to the truly challenging. Each chapter includes exercises that are cumulative, involve literature searches, and require the use of a spreadsheet or the molecular modeling program on the CD that accompanies the text. The exercises are designed to ensure that students learn skills that are important for a modern chemist. Each exercise has been solved and checked independently by ourselves and Professor Whitmire, and by Maxine Bishop and Julie Francis at Rice. 

Student CD-ROM For fast-paced classes like these, we take special pride in our utilities-based CD-ROM. Utilities include what we call living graphs, which allow the user to control parameters, spreadsheet... 

Figure 22-17. Spreadsheet for the determination of the overall formation constant of tris(l,10-phenanthroline)iron(II). (Student data, from E. J. Billo.)...

Our major objective of this text is to provide a thorough background in those chemical principles that are particularly important to analytical chemistry. Second, we want students to develop an appreciation for the difficult task of judging the accuracy and precision of experimental data and to show how these judgments can be sharpened by the application of statistical methods. Our third aim is to introduce a wide range of techniques that are useful in modern analytical chemistry. Additionally, our hope is that with the help of this book, students will develop the skills necessary to solve analytical problems in a quantitative manner, particularly with the aid of the spreadsheet tools that are so commonly available. Finally, we aim to teach those laboratory skills that will give students confidence in their ability to obtain high-quality analytical data. 

Spreadsheet Applications. Applications of Microsoft Excel in Analytical Chemistry, by Stanley R. Crouch and F. James Holler, treats in detail the spreadsheet approaches summarized in the text. This supplement contains 16 chapters that lead the student from basic concepts and operations to using spreadsheets for simulations, curve fitting, data smoothing, curve resolution, and many other topics. Topics in this companion book are correlated with topics in the text. See pages xvii and xviii for a correlation chart. Summaries in the text point to specific chapters and sections in the companion book. For added value and convenience, this ancillary can be packaged with the text. Contact your Thomson Brooks/Cole representative for details. 

Applications of Microsoft Excel in Analytical Chemistry, a clear and concise companion to Fundamentals of Analytical Chemistry, eighth edition, and Analytical Chemistry, An Introduction, seventh edition, provides students and professors with a valuable resource of the most useful spreadsheet methods. Correlation of Spreadsheet Supplement to Texts. The following chart lists cross-references to Fundamentals of Analytical Chemistry, Eighth Edition, and Analytical Chemistry An Introduction, Seventh Edition. 

Statistics teaches that the deviation of data based on less than 30 measurements is not a normal distribution but Student s t-distribution. So it is suitable to express the binding constant K with 95% confidence interval calculated by applying by Student s t-distribution. Student s t-distribution includes the normal distribution. When the number of measurements is more than 30, Student s t-distribution and the normal distribution are practically the same. The actual function of Student s t-distribution is very complicated so that it is rarely used directly. A conventional way to apply Student s t-distribution is to pick up data from the critical value table of Student s t-distribution under consideration of degree of freedom , level of significance and measured data. It is troublesome to repeat this conventional way many times. Most spreadsheet software even for personal computers has the function of Student s t-distribution. Without any tedious work, namely, picking up data from the table, statistical treatment can be applied to experimental results based on Student s t-distribution with the aid of a computer. In Fig. 2.12, an example is shown. When the measurement data are input into the gray cells, answers can be obtained in the cell D18 and D19 instantaneously. 

Fig. 2.12. Spreadsheet for statistical data treatment based on Student s t-distribution.

As a modem chemical engineering student, many of you are computer-sawy. This book assumes that you are not a complete beginner, but have some experience with spreadsheet programs such as Excel. The chapters provide examples and step-by-step instractions for using the computer programs to solve chemical engineering problems. If necessary, you can find more detailed information about the individual programs in the Appendices. 

Divide into teams of two to four students. Work through a spreadsheet (Tables 5.1 and 5.2, and Figs. 5.8, 5.9, and 5.11), with each person of a team taking a unit, showing where the parameters are for that unit and checking the results. Are they correct Work through the whole process. Alternatively, your instructor can prepare a flowsheet and dataset showing the results, but with some errors for your team to find. 

Since the spreadsheet is eminently capable of doing tedious numerical work, exact mathematical expressions are used as much as possible in the examples involving chemical equilibria. Similarly, the treatment of titrations emphasizes the use of exact mathematical relations, which can then be fitted to experimental data. In some of the exercises, the student first computes, say, a make-believe titration curve, complete with simulated noise, and is then asked to extract from that curve the relevant parameters. The make-believe curve is clearly a stand-in for using experimental data, which can be subjected to the very same analysis. 

The aim of this book, then, is to illustrate numerical applications rather than to explain fundamental concepts. Theory is mentioned only insofar as it is needed to define the nomenclature used, or to explain the approach taken. This book can therefore be used in conjunction with a regular textbook in analytical chemistry, in courses on quantitative or instrumental chemical analysis. It can also serve as a stand-alone introduction to modern spreadsheet use for students of chemistry and related scientific disciplines, provided they are already familiar with some of the underlying scientific concepts. Because of its emphasis on exercises, this book is also suitable for individual, home use. 

Arrange the data as shown in spreadsheet 4.8 with one factor going across the columns (the student in this case) and the other factor that contains replicates going down the column (forward or reverse pipetting). 

A comprehensive solutions manual is available for use by instructors and students in which all problems are completely worked out and all questions are answered. Answers for spreadsheet problems, which include the spreadsheets, are given in your CD-ROM. Answers to even-numbered problems are given in Appendix F. 

COMMENT. If numerical methods are to be used to locate the roots of the equation which locates the extrema, then graphical/numerical methods might as well be used to locate the maxima directly. That is, the student may simply have a spreadsheet compute and examine or manipulate the spreadsheet to locate the maxima,... 

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