A Course in Inorganic Preparations

The aims of a course in inorganic preparations are, first, to learn the common techniques and reactions of preparative inorganic chemistry, and second, to become acquainted with the appearance and properties of t3q)ical inorganic substances. This manual has been written with these aims in mind. Fifty-two experiments are described, in which samples of some 70 substances are prepared. The experiments have been chosen to illustrate a varietv of reactions, techniques, and substances. 

Most of the experiments can be performed by a class of 10 or 20 in a laboratory with average facihties, and they need, on the average, about 3 hours working time each. Very long preparations and preparations involving complicated equipment or expensive chemicals have been avoided. It may be desirable for a few students to perform such preparations, but they can always refer for details to the original literature. 

In nearly every experiment in this manual, tests are made on the product to study its properties, and in several instances directions are given for analyzing the product quantitatively to determine its purity. Volumetric methods of assaying are given, since they are quicker than gravimetric methods and often just as accurate. 

A set of questions is appended to each experiment. Some of these questions will be answered by the experiment itself that is, they concern reactions or phenomena that occur in the experiment but are not described explicitly in the directions. Many of the questions involve periodic system relationships, and it is to help answer such questions that Chapters IV and V of the preliminary text are included. There is more system, logic, and correlation to inorganic chemistry than is generally appreciated, and any course in descriptive inorganic chemistry, whether a laboratory course or not, should emphasize this system. It is also important to understand the physical principles used in separating a pure product or in guiding a reaction to obtain the desired substance for this reason Chapters III, VI and VII are included, and a number of the questions on the various experiments concern these principles. Other questions relate to industrial applications. 

After the various tests have been made, the entire product, if a solid or liquid, should be submitted to the instructor in a labeled specimen bottle or suitable container. 

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For a course in inorganic preparations, the equipment that every student should have in his desk is approximately the following ... 

When I started writing this book, it was exactly 50 years ago that I became acquainted with organo-transition metal chemistry. As an undergraduate at the University of Jena in the former Deutsche Demokratische Republik ( East Germany ), I attended a course in preparative inorganic chemistry and a junior colleague of Professor Franz Hein took care of the course. It was at this time, that Professor Ernst Otto Fischer visited Hein s laboratory to inform him that,... 

Chapters V-X deal respectively with Heterocyclic and Alicyclic Compounds Miscellaneous Reactions Organic Reagents in Inorganic and Organic Chemistry Dyestuffs, Indicators and Related Compounds Some Physiologically-Active Compounds and Synthetic Polymers. Many of these preparations are of course intended for advanced students, but a mere perusal of the experimental details of selected preparations by those whose time for experimental work is limited may assist to impress them on the memory. Attention is particularly directed to the chapter... 

Reaction Velocity and Temperature.—Reactions with organic substances take place much more slowly than those which form the subject matter of a course of practical inorganic and analytical chemistry. The latter are nearly always ionic reactions, which proceed with immeasurable rapidity, but organic substances usually react much more slowly and therefore their preparation requires to be accelerated by increased temperature. A rise in the temperature of 10° doubles or trebles the velocity of most reactions. If the velocity at 20° is represented by v, then on the average that at 80° is v x 2 56. Consequently reactions will proceed in boiling alcohol about 250 times as fast as at-room temperature. 

This book is intended to fill this void in the student s training and practical experience by supplementing the anal course in theoretical inorganic chemistry on the level ef college seniors and university graduate students with a. carefully selected and tested collection of compounds which an be prepared with relatively simple equipment and inexpensive materials. Every experiment is designed to familiarise the student with some special aspect of inorganic theory. 

The present book was prepared to provide an introduction to the field of inorganic polymers. There has long been a need for such a book, as opposed to the ready availability of numerous other books, that are highly specialized and written for scientists already working in this area. The only background required for its comprehension are the basic concepts presented in a typical undergraduate course in chemistry. Some famil-iarty with the fundamentals of polymer science would be helpful, but not necessary, since many of these are covered in an introductory chapter on polymer characterization. 

Vni.l INTRODUCTION In many universities and colleges there is not enough time allocated in the curriculum to carry out a full study of qualitative inorganic analysis. For such institutions the abbreviated course, described in the present chapter can be recommended. With good preparation and organization such a course can be completed within 24 to 48 hours net laboratory time. It can also be recommended as a course to those whose main interests lie outside chemistry, but who wish to acquire some knowledge of qualitative inorganic analysis. 

Impurities. Of course, the presence of impurities in a sample will have a dramatic effect on the XRD characteristics. Zeolite preparations, as synthesized, can contain both organic and inorganic impurities. After washing and calcination, many impurities become amorphous, and the resulting XRD powder pattern will clearly show changes from the as-synthesized material. Some impurities, however, are stable to calcination and can make identification and characterization of the material (especially a new material) rather difficult. This is particularly true for cases where only a small number of samples, prepared in a narrow synthesis regime, are available for XRD examination. Common impurities found in zeolite preparations are the stable silicates, quartz and cristobalite. 

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