Introductory experiments involving

The November, 2001 issue of the Journal of Chemical Education (pp. 1533-1534) describes an introductory biochemistry laboratory experiment involving cyclohexanone monooxygenase oxidation of cyclic ketones. 

An introductory chemistry experiment involves heating finely divided copper metal with sulfur to determine the proportions in which the elements react to form copper(II) sulfide. The experiment works well because any excess sulfur beyond that required to react with the copper may be simply boiled away from the reaction container. 

A minimum flux of 1 x n cm s is probably necessary to demonstrate the possibilities in trace element analysis. Simple materials such as pure aluminium, elemental iodine, pure CaCOs or other material may be irradiated and the resultant radioactive half-life measured on an available counting system such as a GM counter, gas flow proportional counter, Nal or Ge detector system. Such an introductory experiment is most appropriate following a lecture and tour of the facility. The tour should emphasize the capabilities and possible usage especially as related to the discipline involved. Frequently, prior to arrival, someone in the discipline (perhaps the class instructor or the students themselves) should be consulted to determine the type of application that would be of interest. This allows the reactor representative to relate to a potential use. 

Phase 0. In this cycle the activities in the first meeting had already led to confusion about the objectives of the course because teachers thought they were involved in a process of improving the details of a new innovative module. They reported in the evaluation that they were the subject of an inquiry. As in the first cycle, the introductory experiment had made teachers enthusiastic about using this approach. 

To facilitate the analysis and before too many conclusions are drawn, it is pointed out here that only the basic theories and major factors involved in diffraction technique suitable for an introductory experiment were treated. Keeping the above and the purpose of this experiment as described in the abstract in mind, the following facts (besides others) should be considered in the student analysis and conclusions of this experiment ... 

In the introductory section to each chapter, there is a brief explanation of the scientific basis of the topic and this is followed by a discussion of the analytical methods which are relevant. While it is not intended that it should be a book of recipes , technical details for many of the methods described are given. This will help those readers with no practical experience to appreciate the steps involved in the analysis while at the same time giving sufficient detail for the method to be developed in practice. It is intended that the book will provide enough information to enable a student to select a technique or series of techniques which would be appropriate for a particular analytical problem and to be able to develop a valid and reliable analytical method. 

Within the broader context of their chosen research project, module authors communicate chemical concepts and introduce students to the research process. Faculty are motivated to write CASPiE modules in part because they recognize the opportunity to teach students the chemistry concepts involved in their own research. One module author described her motivation by saying, I wanted to come up with a very simple and, and very um, elegant experiment that can explain many concepts that are the key concepts of solid state chemistry (Module author 3). Another author, in describing the approach he took to develop the introductory activities, said, I was thinking, are those... 

As described in the Introductory Chapter, attention was focused [1] prior to 1961 mainly on the morphology of the cool-flame and ignition regions, rates were followed by pressure change, and essentially chemical techniques were used for product analysis. The acceptance of free radicals, followed by the masterly and elegant Semenov theory [2], which established the principles of branched chain reactions, provided the foundation for modern interpretations of hydrocarbon oxidation. This chapter builds on these early ideas, and pioneering experiments such as those carried out by Knox and Wells [3] and Zeelenberg and Bickel [4], to provide a detailed account of the reactions, thermochemistry and detailed mechanisms involved in the gas-phase chemistry of hydrocarbon oxidation. 

Most experiments in introductory chemistry courses use hydrophilic solutes with water as the solvent. While there are many chemical reasons for this (such as the solubility of common acids and bases in water), water is also a convenient solvent since it is inexpensive, it is nonflammable, and, if it doesn t have nasty things dissolved in it, it is easy to dispose of by just pouring it down the sink. The transition to organic chemistry traditionally involves a change from hydrophilic chemistry to hydrophobic chemistry in the laboratory. 

As indicated in the introductory remarks to this chapter, significant parts of the equipment for laser chemistry experiments are related to the transport of light between locations and the manipulation of the light beams by optical components. Thus, it is useful to discuss briefly some basic concepts involving the interaction of light with optical components in the beam path, to elucidate the general properties of the materials used and the light waves themselves. 

Thus, the experiments contained in Chapter lOW are specifically tailored to challenge the more advanced undergraduate students, those who are already able to access the chemical literature. This chapter can also offer a special laboratory experience for those few beginning students who are particularly interested in the subject and wish to spend extra preparation time. The techniques involved are not, in most instances, any different from those used in the introductory microscale laboratory reactions described in Chapter 6, and therefore the manipulations involved should not be considered a barrier to undertaking any of the advanced experiments. The reaction conditions, however, are less forgiving to slight deviations from the suggested ones and the ultimate success of the transformations is less secure. 

This laboratory manual assumes that the student has already mastered the introductory laboratory techniques in an introductory course on organic chemistry involving the typical glassware normally used in these preparations. Careful record keeping is a must and is covered in the Appendix. Experience in the various analytical techniques described is also assumed. Experience in distillations, both at atmospheric pressure and under reduced pressure, is also assumed. 

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