Laboratory work Chemistry courses

The material in this text assumes familiarity with topics covered in the courses and laboratory work you have already completed. This chapter provides a review of equilibrium chemistry. Much of the material in this chapter should be familiar to you, but other ideas are natural extensions of familiar topics. 

CHEMISTR Y—An Experimental Science presents chemistry as it is today. It does so with emphasis upon the most enjoyable part of chemistry experimentation. Unifying principles are developed, as is appropriate in a modern chemistry course, with the laboratory work providing the basis for this development. When we are familiar with these widely applicable principles we no longer have need for endless memorization of innumerable chemical facts. To see these principles grow out of observations you have made... 

The Scholars, working with their mentors, did an outstanding job during their residencies, and many laboratory experiments and new lecture snapshots were developed. Lecture snapshots are short discussions of timely or fundamental polymer topics. They are designed to minimize the time necessary for faculty to familiarize themselves with the topic and to prepare their presentation on it In general, the lecture snapshots require only a few minutes of lecture time and setup and interface with topics that already are covered in general chemistry courses. The snapshot format is as follows ... 

While the pieces of equipment mentioned above are now commonplace, it remains for the analysts to be well informed of potential dangers and of appropriate safety measures. To this end, we list below some safety tips of which any laboratory worker must be aware. This list should be studied carefully by all students who have chosen to enroll in an analytical chemistry course. This is not intended to be a complete list, however. Students should consult with their instructor in order to establish safety ground rules for the particular laboratory in which they will be working. Total awareness of hazards and dangers and what to do in case of an accident is the responsibility of the student and the instructor. 

You will receive a test booklet for the free-response section of the test. You will have 95 minutes to answer six questions. These questions may cover any of the material in the AP Chemistry course. Section II consists of two parts. In the first part, you may use a calculator. You will have 55 minutes to answer three questions, the first of which will deal with equilibrium. In the second part, you may not use a calculator. You will have 40 minutes to answer three questions, the first of which will be a reaction question. One of the free-response questions will address laboratory work. The first part will account for 60% of your... 

For me, nothing illustrates this chasm between observation and chemical theory better than my experiences as a teaching assistant in the laboratory of a beginning chemistry course. Students were carefully following procedures described in the lab manuals, filling in the blanks to describe their observations. Then as a kind of climax they were asked to Write the equation for this reaction. Students were often stunned by this request, for they could perceive no connection between what they had observed and the equation they were expected to write. This gap between the perceptual experience of events and their conceptual representation is wider and deeper than for any other of the basic sciences. That fact in large part accounts for the late arrival of chemistry at its maturity, with the work of John Dalton early in the nineteenth century. 

An integral part of a student s education in physical chemistry is laboratory/practical work. While it is generally accepted that the main purposes of laboratory work are to teach hand skills and to illustrate theory, significant problems have been identified in the science education literature about the laboratory courses, and in particular about the ineffectiveness of laboratory instruction in enhancing conceptual understanding (135, 136), and unrealistic in its portrayal of scientific experimentation (137). 

Computational chemistry is essential in a modem physical chemistry course. One approach would be to use laboratory time to have students work through a number of exercises accompanied by elaboration of the concepts in lecture or pre-laboratory discussions. Each of die major computational chemistry software packages come with workbooks or tutorials for learning the software. For example, students can learn by completing exercises in the Spartan tutorials (57). Similar approaches can be taken when using Gaussian (38) and Hyperchem (39) tutorial or exercise collections. 

Admittedly then, none of these courses serves to train tbs student in the fundamental techniques and problems of preparing inorganic chemicals. This is in direct contrast to tbs study of organic chemistry in which laboratory work is extensively stressed. The point is reached in the student s training where he can no longer think of preparative work except in terms of the chemistry of carbon compounds. 

All students entering the Massachusetts Institute of Technology should have met an entrance requirement in chemistry. It is very discouraging to such students to be set at once to reviewing what they have already had, however much they may need the review. The nature, and the considerable freedom in the choice, of laboratory work solves this situation in a very satisfactory manner. A review of preparatory school work is of course necessary, but by bringing this in incidentally the sting of it is removed. 

For this reason, lecture courses in physical chemistry are usually accompanied by a program of laboratory work. Such experimental work should not just demonstrate established principles but should also develop research aptitudes by providing experience with the kind of measurements that can yield important new results. This book attempts to achieve that goal. Its aim is to provide a clear understanding of the principles of important experimental methods, the design of basic apparatus, the plaiming of experimental procedures, and the significance of the final results. In short, the aim is to help you become a productive research scientist. 

All knowledge and theory in science has originated from practical observation and experimentation this is equally true for disciplines as diverse as analysis and synthesis. Laboratory work is an essential part of all chemistry courses and often accounts for a significant proportion of the assessment marks. This book aims to provide an easy-to-use reference source dealing with basic practical techniques and information. The skills developed in practical classes will continue to be useful throughout your course and beyond, some within science and others in any career you choose. 

It is possible to reduce the cost of teaching a laboratory-based chemistry curriculum by using small scale techniques. It is also important to consider how much and what chemicals are to be used. Small-scale techniques are generally more safe and they also help to improve the manipulative skills of the students. Texts indicating how small-scale work can be used through out a school course have been published in many a countries. 

No course in chemistry can be considered as complete without including some practical work in it. The practical work is to be carried out by individual in a chemistry laboratory. Most of the achievements of modern chemistry are due to the application of the experimental method. At school stage practical work is even more important because of the fact that we learn by doing scientific principles and applications are thus rendered more meaningful. It is a well known fact that an object handled impresses itself more firmly on the mind than an object merely seen from a distance or in an illustrations. Centuries of purely deductive work did not produce the same utilitarian results as a few decades of experimental work. Practical class room experiments help in broadening pupil s experience and develop initiative, resourcefulness and cooperation. Because of the reasons discussed above practical work forms a prominent feature in any chemistry course. 

Two other features of the course structure deserve comment First, there is a heavy emphasis on laboratory work, since high school teachers of chemistry are often insufficiently prepared to run labs safely, economically, and efficiently. Second, there is a decided thrust of all the courses in the direction of practical chemistry (demonstrations, molecular basis of devices, consumer chemicals) to enable the teacher to teach relevant chemistry in a less-than-optimal environment The intent is to equip the teacher to solve the real problems of teaching in a setting where equipment is primitive, support is minimal, facilities are inadequate, and professional isolation prevails. 

More than any other researcher in a department of chemistry, the scholarly work of the chemical education researcher will be influenced by both the research and educational missions of the department and of the institution. The research mission of the department will have an impact on the expectations that will exist for scholarly work in the area of chemical education. It is not fair to oversimplify the situation by saying that institutions with less research emphasis will expect less research from a chemical education researcher and those with a heavy research emphasis will expect more. Indeed, many departments with a heavy research emphasis do not consider their chemical education researchers to be researchers in chemistry, and in some cases do not expect them to be. For example, there are institutions who hire a specialist in chemical education to direct a large undergraduate education program, sometimes consisting of many hundreds of students who will be enrolled in first and second year chemistry courses with laboratory components. Likewise, smaller institutions, where there is less traditional chemistry research, may be interested in emphasizing research... 

Who should read this book Students who anticipate performing TEQA will find the content very beneficial. This includes students at universities and four-year colleges that offer an analytical chemistry course with an environmental emphasis. As we have found at Michigan State University, there is a real need to teach incoming graduate students the principles encompassed in this book. The book also serves the practicing analytical chemist who works in an environmental testing laboratory or equivalent. 

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