First-year college chemistry textbooks: Through the 20th century

First-year college chemistry textbooks: Through the 20th century ... A study of nine American textbooks for beginning college chemistry over ... Cover...
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First-Year College Chemistry Textbooks Through the 20th Century John C. Bailar, ~ r ? University of Illinois, Urbana, IL 61801 This paper reports a study of nine American textbooks for beginning college chemistry over three-fourths of this century. The books are Holleman, A. F. Inorganic Chemistry, 4th ed.; Cooper, H. C., Transl. and Ed.; Wiley: New York, 1916. Kendall, J.Smith$ Inorganic Chemistry, 4th ed.; The Century Co.: NewYork. 1926. Hopkins, B. S. General Chemistry for Colleges, 1st ed.; D. C. Heath: Boston, 1928. Hookins. B. S. General Chemistri . .for Colleees. - . 3rd ed.: D. C. - ~ e a t hBastan, : 1942. Sanderson, R. T.Principles of Chemistry; Wiley: New York, 1963. Pauling, L. College Chemistry, 3rd ed.; W. H. Freeman: San Francisco, 1964. Masterton, W. L.; Slowinski, E. J. Chemical Principks, 3rd ed.; Saunders: Philadelphia, 1973. Busch, D. H.; Shull, H.; Conley, R. T. Chemistry; Allyn and Bawn: Boston, 1973. Zumdahl, S. S. Chemistry, 2nd ed.; D. C. Heath: Lexingtan, MA, 1989. No claim is made that these books are representative of the ueriods a t which thev were oublished. but thev certainiy show the general t&ds that were t a k n g place. The titles alone are indicat~ve.The first two are labelled Iuorganic Chemistry, but two of the later ones are entitled Princi~les.The Pauling and Zumdahl books are not so titled, gut even a brief examination tells one that principles are emuhasized rather than descriutive inorganic chemistry. The text by Holleman was originally written in Dutch, but in his translation, Cooper edited it markedly, so that it represents what was going on in American chemistry a t that time. The text was the one used by the author of this paper in his first year of college chemistry. There was a companion volume entitled Organic Chemistry that was used in the second-year course. The book described here is almost purely descriptive inorganic chemistry and is written in simple language. After a n introduction of eight pages on the general nature of chemistry, the author goes a t once into a description of oxygen and oxidation. Hydrogen is described next (preparation, physical properties, chemical properties, uses), then a short discussion of the conservation of matter, including two paragraphs on the beliefs of the ancient Greek '~eceasedOctober 17,1991.

philosophers on this subject. Next follows a section on water-physical and chemical properties, purification, the composition of water-and then, on page 27, the law of constant composition and the atomic theory. Symbols and formulas are described in some detail, with the formulas of hydrogen, oxygen, and chlorine in equations written a s H, 0 , and C1. (In later pages, these are usually doubled-especially, but not always, after the introduction of Avogadro's law on page 45).Rules for the determination of molecular and atomic weights follow and then a discussion entitled "The Reality of Molecules and Atoms and Their Absolute Weight." Ozone and hydrogen peroxide are described in eight pages in the usual sequence--preparation, physical properties, chemical properties, uses. (For substances that occur in nature, a section on "occurrence" usually precedes these topics). Charles' Law and Bovle's Law follow. and then a section on the determination*of molecular weights by measurement of boiling uoint elevation and freezing depression. -. - point . The elements are described, one by one, with their important properties and compounds (and sometimes, unimportant ones). The "physical chemical" aspects, such as reaction rates, are discussed as they are needed to explain urouerties or reactions. The theorv of ionization is dis&Led a t length, with the assumPCion that the degree of ionization. even for HCI. deuends uuon the concentration of the solkion. The book speaks of hydrogen atoms and chlorine atoms in the solution. Gibbs' phase rule, which does not appear a t all in most of the more recent books, is discussed in some detail, in connection with the allotropic forms of sulfur. Fourteen pages are devoted to the nine oxyacids of sulfur. Selenium gets two pages and tellurium, one. The chemistry of nitrogen and its compounds is discussed in detail-ammonia, hydrazine, hydrazoic acid, hydroxylamine, nitrogen halides, the five oxides of nitrogen, the five oxyacids (including a long discussion of the arc process for making nitric acid, but only three lines on the preparation from ammonia). Nitrogen and its compounds occupy 34 pages. Phosphorus and its compounds are discussed on the following 22 pages. The rest of the elements follow, even less common ones like beryllium and gallium getting brief descriptions. The description of the periodic table (in the old, short form as well a s Lothar Meyer's table) first appears more than half way through the book, aRer a detailed description of methods of determining atomic weights by the Volume 70 Number 9 September 1993

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use of DuLong and Petit's and Mitschedich's Laws. Several pages are devoted to electrochemistry. These sections are followed by a discussion of electron theory based upon a description of spectroscopic methods. In the words of the author: The physical investigations since the beginning of this century have furnished substantial reasons for believing that the chemical atoms are not in reality the ultimate particles of matter, hut that they are divisible into particles approximately 2000 times smaller than the hydrogen atom. These particles, carrying with them, as they do, very strong electrical charges, are called eleetrnns. . . . [Tlhe chlorine ion, for example, wnsists of chlorine and an electron-the cations are formed from the atoms by the release of one or more electrons. It is stated that electrons have no mass. Radioactivitv and isoto~esare discussed a t len&h, coneluding with a"paragraph'in which it is specnlate&that all elements mav be radioactive. but that the decay of most of them is so slow that i t has not been detected. Again quoting from the book: ~

So far as we know, the radioactive transformations are irreversible. We can only stand by and look on; we can neither produce nor stop them. If these changes should prove to he a general property of matter, it would mean that all matter is engaged in slow decay.

tremendous success and was translated into many foreign languages, including Russian and Chinese. The other textbooks of the time were based largely on his plan. There were several subsequent editions and after Smith's death; they were edited and kept up to date for some years by James Kendall of New York University. The Smith book which I am reviewing here is the fourth edition, copyrighted in 1926.It is a much larger volume than the one by Holleman, containing over a thousand pages. After an introduction on the chemical view of matter, chemical change, and the occurrence of the elements, there are successive sections on the Law of Multiple Proportions, the Law of DuLong and Petit, crvstal forms, X-ray crystal analysis and s$mbols, and formulas and equations: The discussion of crystal structure is quite extensive, but, of course, contains no suggestion of the existence of ions in the crystal. The first "descriptive"chemistry concerns the history, occurrence, preparation, physical properties, and chemical properties of oxygen. This is followed by successive chapters on gases, hydrogen, and water. Interspersed in these chapters are discussions on valence, symbols, formulas, and equivalent weights. The subject of molecular weights occupies 27 pages and the chapter on solutions, 30 pages. The author then returns to the descriptive chemistry of hydroeen chloride and sodium hvdroxide. C h a ~ t e r son energy and chemical changes, chemical equilibrium, acids, bases, and salts, and ionization follow. A rather long chapter on oxidizing substances discusses ozone, hydrogen peroxide, hypochlorites, dichromate, and permanganate. It is stated that ~~~

The book closes with a two-page description of atomic structure. I suspect that this was added when the writing of the m a n ~ s c r ; ~was t otherwise complete--perhaps even promess. The following passage while the printing- was in . appears: ~

~

According to Rutherford, an atom consists of a positively chatzed nucleus surrounded by negative electrons, which are arranged in eoncentnc rings ' f i e u r muf the negative charhw is numenually equal m the positive char e ufthr nucleus. The nucleus has n radlud ofthe order of 10.' f cm. while the radlus ~~~~~-~~ of the outermost electron ring is about 10" c k ~

The concept of atomic number is then introduced and the virtues of the new theory in clearing up the discrepancies in the periodic tables are extolled. somi people say that the study of descriptive chemistry is dull and borine. For me. Holleman's book was extremely interesting. I really learned inorganic chemistry-the nature and hehavior of the elements and their compounds. I frequently wonder if we wouldn't attract more-students into the chemical fold by giving them this sort of introduction to the subject. At least it would give them the feeling that chemistry is useful. I wonder whether they get that feeling from a long discussion of theory. I t may not be important that students know how to prepare sulfuric or nitric acid, but they should learn how these compounds behave, and that they are important to modem civilization. As chemistry advances and new discoveries are made, authors naturally want to include the new material in their texts. Yet there is a reluctance to leave out the old t i e d and true material which has been taught for many vears. Different authors handle this problem in different ;rays. Some boldly omit topics that thky consider of lesser imoortance--for example. the preparation of sulfuric acid. ~ h k s eauthors tend to'empha&~principlesa t the cost of descri~tivechemistrv. Others attempt the de. to generalize . scriptive aspects, thus saving some space. Still others include both the old and the new, leaving it to each individual teacher to select the subject matte; to be emphasized. Whereas the older books discussed only inorganic chemiatry, the newer ones tend to include organic and biochemistry as well. This, too, demands a bigger book. ~ l e x a n d e r ~ m iwasonc th of the&&test, if not the greatest, wrlter of aeneral chemistry textbooks in the early part of this centu& His first text,-copyrighted in 1905,was a

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if. . . we write the equation ionically

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Zn + 2Hi +2n% + H2 we discover that logically we must wnsider the change from metallic zinc to zine-ion to be in itself oxidation. Seven pages are devoted to the chamber process for making sulfuric acid, but there is no mention ofthe contact process. As in the Holleman text, the other oxyacids of sulfur are all included. The chapter on the periodic system does not appear until we are half way through the book. This is followed by a long chapter entitled "Radium, Atomic Energy and Atomic Structure" in which the atoms of the lighter elements are first shown as cubes which share comers in compound formation. However, the Bohr theory is also covered in some detail. The chemistry of nitrogen and the atmosphere is covered in three chapters, including a considerable discussion of the Haber Process and the preparation of nitric acid from ammonia. After a chapter on the "inorganic" chemistry of carbon, there is a chapter on "The Hydrocarbons and Their Derivatives". and then 300 Daees on the chemistw of the metals, each taken up in th; &der-occurrence, ireparation, properties, uses, compounds, and uses of the compounds. The isomeric chromic chloride hydrates are accorded a page as are the cobalt ammines. The first and third editions of Hopkins' General Chemistry for Colleges were published 14 years apart (1928and 1942)and show some marked differences. The earlier edition "Part I"., but.. as far as I know. Part I1 was ~ - ~is - marked never written. Part I does not include the chemistry of the metals. In the first edition. the c h a ~ t eon r atomic structure appears three fourths of the way through t h e book; whereas, in the 1942 edition, it is in Chapter 2. The 1928 edition shows the atoms as cubes which share comers in compound formation, but the later edition shows them as circles and ellipses. Not surprisingly, the first edition contains no mention of neutrons, because they were not dis~~

covered until 1932. In neither edition does the author make much use of atomic structure in the explanation of chemical reactions. In the first edition, the discussion of the periodic table appears in the latter half of this book, but in the third edition. it follows immediately after the chapter on atnnuc structure, and is based in a ieneral way on the structure ofatoms. The first edition states that salts ionize when dissolved in water, but the third edition indicates that even solid salts consist of ions. Both books use the short form of the periodic table. Both follow Alexander Smith's nlan of startine the studv of descriptive chemistry with oxygen, ozone, hydrogen, water, solutions. and hvdroeen neroxide. with the gas laws and lunet~ctheory &erted. ~ o l l o ~are d s even several pages in each book The first edition devotes a half a page to the preparation of nitric acid from ammonia, but gives two pages to the arc process. However, in the third edition these are reversed. The preparation from ammonia gets one page and the arc process, a half page. In both editions, the preparation of sulfuric acid by the contact process is allotted one page and the lead chamber process, three pages, and both editions devote seven pages to the acids of phosphorus. Neither of these books gives any space to organic chemistry. Significantly,Sanderson's book, published in 1963, is titled Principles of Chemistry and marks a change from emphasis on the descriptive aspects to emphasis on principles. There are still descriptive chapters in the usual order: oxygen, water, hydrogen peroxide, hydrogen, hydrides (including lithium, beryllium and boron hydrides), and chlorine, but these do not appear until one is a third of the way through the book. Another chapter on descriptive chemistry is found near the end of the book. It is devoted to the production of metals. The flotation process is described briefly and two pages are devoted to the blast furnace for the reduction of iron oxide, but there is no mention of the production of steel from pig iron. The electrolytic purification of copper is described briefly in a rather extensive chapter on electrochemistry. The early chapters of Sanderson's book are devoted to atomic structure, chemical bonding, physical states and physical properties of the elements, properties of gases, the periodic table, formulas and equations, bonding, and oxidation and reduction. Chapter 3, devoted to atomic structure, includes discussion of spectral series and quantum numbers and the following chapter introduces such tonics as X-rav diffraction. electron diffraction. microwave s~ectroscopy,hybridization, and resonance. ~ e t a l l i bondc ine and van der Wads forces annear in C h a ~ t e5. r The language throughout this book is noticeably more sophisticated than in the earlier books. This tendency is evident in most of the more recent books. also. Whether "principles" are not easily discussed in simple language, or whether the authors feel that modern students can understand more sophisticated language is not clear Sanderson's book, like most of the others, has a chapter on the neriodic table. Unlike the earlier books, however. the autkor gives no space to its historical development, ap: proaching the subject from the atomic structure point of view. Atomic radius, ionic bonding, bond angles, and protonic bridging (hydrogen bonding) are discussed in turn. Zinc sulfide is described as an example of an inorganic polymer, by which is meant that this substance does not exifit as diicrete molecules. There is also a section on the mechanism of the reactions of hydrogen with chlorine and with iodine. Sanderson differs from the earlier authors in including chapters on organic chemistry and nuclear reactions, a plan which most of the later authors use, also. The third edition of Pauling's College Chemistry appeared in 1964. It is quite different from any of the other

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books discussed here in that atomic and molecular structure permeate the entire text. After a few pages of general introduction on the nature of chemistry, the author launches into a discussion of atomic and molecular structure, including w s t a l structure, atomic nuclei, radioactivity, and the wave nature of the electron. The author then goes into a more conventional description of the elements, the determination of atomic weights,weighkweight calculations, and the descriptive chemistry of hydrogen and oxygen, followed by the gas laws and kinetic theory. Like Sanderson, Pauling develops the discussion of the periodic table from the structure of atoms. r oreanic chemistrv immediatelv follows the A c h a ~ t e on one on the inorganic compounds of carbon, and a more detailed discussion of oreanic chemistry is introduced later in the book. The chemistry of the elements is introduced as we cross the periodic table, but it is interspersed with more esoteric material such as discussions of liquid ammonia as a solvent, softening of water by zeolites, the hydrogen bond, clathrates, and ionic activity Colloids are given only one page, but the phase rule is accorded three (in the section on alloys). The section of Pauling's book which deals with the metals contains a good deal of descriptive and industrial chemistry. The book closes with chapters on biochemistry, the chemistry of the fundamental particles (mesons, photons, et~.),and nuclear chemistry Masterton and Slowinski quite properly entitled their 1973 book Chemical Principles. It contains some descriptive chemistry, but nearly all of this is from the "principles" point of view. ARer an introductory chapter, the authors go directly to a brief discussion of atomic structure. Thermochemistry is introduced early in the book, then a description of the properties of gases, to be followed by 80 pages on atomic structure and bonding. Thermodynamics and equilibrium each take up 25 pages, acid and base theory about 50 pages. Complexes (coordination compounds) are described in some detail from the point of view of both the valence bond theory and the crystal field theory Electrochemistry is discussed in detail, including the production of sodium, aluminium, sodium hydroxide (and chlorine and hydrogen), and the corrosion of iron. This book, like most of the "modern" ones, contains chapters on organic chemistry, biochemistry, and nuclear reactions. Busch, Shull, and Conley have produced a large book which seems to me to demand more of the student; that is, the language is more sophisticated and the number of new words and the number of mathematical expressions are greater than in the books previously mentioned. This book opens with a discussion of the atomic nucleus and builds up the periodicity of the elements from that point of view. There is no mention of the historical development of the periodic table. There is only a brief reference to Mendeleeff, and none a t all to Lothar Meyer. Indeed, almost no attention is paid to the historical development of chemistry. On the other hand, there are chapters on organic chemistry and biochemistry. Like most of the recent books, Busch, Shull, and Conley is a big book (900 pages), but the authors expect the students to cover it inone school year. The flavor of the book can perhaps be conveyed by mentioning a few paragraph headings-"three center bonds", "molecular orbitals", "isomers of inorganic complexes", "ionic radii", "defect solid state", "Br$nsted theory", "Lewis theory", "second and third laws of thermodynamics", "polyprotic acids", "saline hydrides", "covalent hydrides", "organometallics", "polymers", "terpenes", and "steroids." Zumdahl's book (2nd ed., 19891,like that of Busch, Shull and Conley, is a big book (more than a thousand pagesba trend that seems to be general. Like several of the recent books, it is illustrated with four-color pictures. After a

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chapter or two of general material, the author launches at once into atomic structure. There is very little on the development of the ideas of atomic structure or the periodic table, which follows immediately. Such topics as percent composition, chemical equations, limiting reactants, strong and weak electrolytes, and molarity receive early consideration, after which the ideas of atomic structure are given extensive consideration again. This and closely related topics occupy more than an eighth of the book. X-ray analysis, bonding in metals, alloys, phase diagrams, colloids, strength of acids and bases, buffers, entropy, and free energy are all taken up in turn. This is the sort of material which I was taught in my junior year in college. Throughout the book, properties are used to illustrate the prindples of chemistry. Like most of the recently published texts, this book closes with extensive discussions of coordination compounds, nuclear chemistry, organic chemistry, biochemistry, and industrial chemistry. The last even includes a section on the manufacture of wine. Several of the recently published texts are accompanied by supplementary books--problem books, study guides, teachers manuals, and the like. Perhaps these are needed,

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since general chemistry has become more advanced than in earlier years. At least, the publishers seem to think so. So, what has changed? Practically everything. The historical approach to chemical theory has been almost completely abandoned. I regret this, for I agree with the author who wrote, "He who knows only his own generation remains always a child." The earliest book mentioned in this paper was concerned almost entirely with descriptive inorganic chemistry. The theory that was presented occupied a small portion of the book, and was presented from a historical p i n t of view. No problems were presented for student practice. There were no illustrations except for a few graphs and diagrams. There was almost nothing on atomic or molecular structure and, of course, nothing on nuclear chemistry. The switch to emphasis on chemical principles came rather abruptly about 30 years ago, and the proportion of pages devoted to descriptive chemistry has diminished gradually since that time. Simultaneously, the amount of space devoted to organic and biochemistry has increased. One wonders whether the students may not feel swamped and diswuraged by the vast amount of material that they are expected to learn in their fwst college year.