The Coming Renaissance of Descriptive Chemistry J. J. Zuckerman University of Oklahoma, Norman, OK 73019 The trouble with chemists is that chemistry is t m hard for them. Albert Einstein (1879-1955)
Inorganic chemistry is facing an identity crisis. The old jumble of facts has given way to a new jumble of theories. Worse still, the distinction between fact and theory itself has been allowed to blur. Inorganic chemists have been coaxed away from their formerly strong, central position based on a monopoly of information on syntheses, reactions, and properties of the elements and their compounds by the more ephemeral allure and false sophistication of spectroscopy and theory. Colleagues in cognate disciplines can no longer turn to the inorganic chemists for the preps and props knowledge that once was the essence of inorganic chemistry. Freshmen chemistry teaching, once an exclusive province, has, with its subject matter, been allowed t o slip into the hands of physical chemists whose numbers then expanded to meet the new responsibility, taking academic jobs once held by inorganic chemists. Meanwhile, industrial inorganic chemistry became relegated to oblivion as pictures of real blast furnaces and the like in the old textbooks were replaced by pictures of imaginary orhitals and the like in the new. Following the lead of their college and university peers, teachers of high school chemistry no longer teach their students descriptive inorganic material. They, too, prefer instead the nominal principles, such as they are, which lack rigor and predictive abilitv. Facts which refuse to conform to thkse prematurely formulated generalizations are forgotten or suppressed. Inorganic chemists have abandoned their role as caiitakerl of the~uhjectmatter of their own discipline. Rut now distinguished committeeaofelders in the learned societies are calline for curricular reform in inoreanic chemistry. This is perczved negatively by the inorgank chemists, when in fact i t presents a ereat o ~ ~ o r t u n ifor t v the restoration of their discipline to 2 s fomLr high position. The challenge must first be met by the textbook writers who can shape curriculum most directly. Authors and publishers entering the fast-moving current do so a t their peril, since no one can predict the future situation with certainty. Into this market a t the advanced course level N. N. Greenwood (1925- ) and A. Earnshaw (1934- )have inserted astrong statement on the side of facts with their vast magnum opus, "Chemistry of the Elements" (Pergamon Press: Oxford, 1984). Now this source, along with the descriptive parts of other texts currently availahle as well as multivolume works such as "Inorganic Reactions and Methods" (VCH: Weinheim. Germanv. Vol. 1. 1985) will form the basic hodv of mateiial from khich authors ;an fashion books for the general chemistry course. For the solution t o the current difiiculties confronting inorganic chemistry lies in recapturing a significant portion of the freshman syllabus for the study of descriptive information. An acceptable compromise a t this stage would be to use the second semester of the freshman year for this purpose. This proposal is elaborated below. Facts and Theorles I pass with relief from the tossing sea of Cause and Theory to the firm ground of Result and Fact. Sir Winston S. Churchill (1874-1965) in "The Malakand Field Force"
I t is obvious which of the above choices our discipline chooses. Perusal of any current issue of Inorganic Chemistry or other representative journals in the field reveals the imbalanced apportioning between new syntheses, balanced equations supported b y mass-halance-data and physical properties of the new compositions of matter formed in these reactions, on the one hand, and the spectroscopic data and data from other physics-based measurements and theory derived numbers, on the other. Reflecting this situation in research, the most popular texts for the first-year course seem almost to be written as junior primers for a subsequent physical-chemistry course. The premise seems to be that if one knows the ~ . h.v s i c a l principlesgoverning the behavior of matter, then the way is ooen for deriving all of descriptive chemistrv. This is a vast o;erextension of physicist P&I A. M. ~ i r a c ' s(1902-1984) assertion of 60 years ago that The underlying physical laws necessary for the mathematical theory of a large part of physics and all of chemistry are [now] completely known hut has apparently been taken t o heart by teachers of freshman chemistry who reason that if it can be derived, i t need not be taught. How did this come about? A Brid History ol Freshman Chemical Education
It is indeed amystery [remarkedWatson].What do youimagine it means? I have no data yet [responded Holmes]. It is s capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. Sir Arthur Canon Doyle (1859-1930) in "Sherlock Holmes"
The commission to write a textbook that London publishers Longman, Green gave to Dimitri I. Mendeleev (18341907) resulted in his incandescent proposal of the periodic system of the elements and the publication of his "Principles of Chemistry" which was to become the best-selling and most influential textbook of the 19th Century. The periodic table, which had to await the discovery of the electron and the developments of 20th Century physics for its rational basis, provided chemists with a vast correlation of facts and, incidentally, a superior and very effective mnemonic. The most powerful text of the 20th Century thus far (only 14 years left t o go now!) has been Linus Pauling's (1901- ) "Nature of the Chemical Bond" (1st ed., 1939), based on his Baker Lectures at Cornell University that year. This book introduced electronegativity, various types of radii, hybridization of atomic orbitals, resonance, percent ionic character of bonds, ete., to the practicing chemist, and greatly expanded correlations and/ormnemonics availahle in chemical oractice. From this masteroiece was derived a freshman textbook which broke the triditionofthe p a t when the t'irst year was devoted to the study of the elements and their compoundi, syntheses, and reactions, the winning of the metals from their ores and other key industrial processes, etc. 'l'his material wan now joined by extensive chapters on atomic structure, bonding, etc. The balance between cause and effert had taken a giant swing toward the enterprise of generalization and rationalization. Two enterprising young inorganic faculty members at Cornell. M. d. Sienko (192% Volume 63 Number 10 October 1986
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1984) and R. A. Plane (1927- ). nroduced a text based on ~ a u l i n g ' steachings, a n d t h i ' s i e n k o a n d Plane texts (McGraw-Hill). sweot . the freshman market and became ultimately the world's largest-selling chemistry hooks. PostSputnik high school curricular reform brought forth the Chemical Bond Approach replacing the previous fact-based descriptive material. Laboratory work shifted from preparations of chemicals and the old Bunsen qualitative-analysis scheme based on the solubilities of the sulfides to experiments designed todemonstrate the validity of the principles being taught in the lectures. And the process is still going on. One of the must insidious and nefarious properties of scientific modelr is their tendency to take over, and sometimes supplant, reality. Erwin Chnrgoff (1905- ) The distinction between fact and theory has now been so smeared our and the lines of demarcation so blurred that the appreciation that there is a difference a t all is lost. The Premature Leap to Generellzatlon It is a stress for many chemists not to possess a fixed set of axioms. ..for everything, and they are willing to accept an imitation lastine for their lifetime. After all.. manv . moole prefer Khomeiny rather than Hamlet. Christian Klirbull J#rgensen (1931- ) T h e goal of generality in science is legitimate, and the pursuit of unifying principles is a laudatory enterprise. The teaching of the results of these efforts, even to beginning students is a salutarv exercise and is to be encouraeed. However, the situation & inorganic chemistry today that our theories and models are inadequate to the task of explaining the facts. T h e principles available to guide us are overly simplistic and fail to predict or even in some cases to rationalize the known chemistry. T h e truth of the matter is that almost no set of phenomena is well-behaved, and there are so many more anokalies than remlarities that nearly everything needs to be treated as a special case. ~ o n i d e a l ~ t iand e s defect states abound (who or what is defective or nonideal? Nut Mother Nature!). The old catalog of unrelated facts has given way to even more jumbled mish-mash of models, theories, rationalizations, and effects piled high upon one another. I n teaching, the old three-step in which
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You tells 'em what your goin' to teach 'em; You teaches 'em; and You tells 'em what you taught 'em. is now replaced by You teaches 'em; You tells 'em what you taught 'em was wrong; You teaches 'em again; etc. in an enterprise that has an infinity of steps. Thou givest; thou takest away what thou hast given. Neglected F a d s False facts are highly injurious to the progress of science, for they often endure long; but false views, if supported by some evidence, do little harm, for everyone takes a salutary pleasure in proving their falseness; and when this is done, one path towards error is closed and the road to truth is often at the same time opened. Charles Darwin (1809-1882) Let it not be feared that erroneous deductions may he made from recorded fads: the errors arising from the absence of fsds are far more numerous and durable than those which result from unsound reasoning respecting true data. Charles Bobbage (1792-1871) Journal of Chemical Education
Having learned inadequate theories, we suppress the facts which refuse to conform. Even a short list of the inadequacies will come as a shock to some. Here are some neglected facts: (1) Something like a quarter of the ground-state, gas-phase elec-
tron cunfigurationsof theelementsareanomalous in nut obey. ing the combination of the Aufbau principle and Hund'a rule. r2) . . That the transition ntetalsformdi~ositireiunshv lossof twos. orbital electrons is nowhere adeq"ate1y explained. (31 There ia no general theorv to exolain the structure. bondine. and phystcaipropenres aithe H$ mulerule or of bulk water" (41 Photoelectron spectra of gaseuus molerule, are conspicuously unable to detect two or more lone pairs of electrons demanded by the Lewis paradigm, for example, in water or XeF+ Thus, there is no physical basis for the view that there are two separately Localized pairs of non-bonded electrons at the oxygen atom in the Hz0 molecule. (5) The internuclear distance in the Hzmolecule cannot be wed as the basis for the covalent radii of hydrogen since it is too Long, which would make all radii sums derived from it too Long and all actual element-hydrogen internuclear distances appear to be too short. The same is true for the fluorine molecule. The covalent radius of nitrogen is obtained from the C-N distance in methylamine rather than from the N-N bond in hydrazine for similar reasons (6) The order of acid strengths of the simple hydrogen halides in water is opposite to that reasonably expected on the basis of halogen electronegativities and the resulting polarization of the H-X bond. In fact, the acidities of all the main-group binary hydrides increase descending their groups. (7) The radius-ratio rules for predicting solid-state structures formed by the packing of ions fail to predict the correct coordination numbers and geometries. (8) The.fluorinemolecule is anomalously weak (amall hond energy, long bond, Low stretching force constant). (9) The properties of the first-row elements, lithium to fluorine, are anomalous when compared with their heavier congeners. (10) The molecular formulasof the simple, binary thud main-group hydrides and halides follow no regular pattern. (11) That the thermal conductivity of diamond is highest of any material would not have been predicted. (12) The group-IIA halides should be linear on the basis of sphybridization, yet the heavier congeners are bent. Recent theory predicts BeHz to be bent, when it is probably linear. 113) Maenesium metal burns in axveen to eke Me0 and lithium eiv& Li-0. hut sodium eives Nib. e~ ~ .&ootass&n ~ . . ~ eives KO". (14) The basir fur many separarions nominally baaed upon differel~tialrolubility-productconstants ~therm#,dynamr~s~ is in fact kinetic. Likewise, it is often rate differences that allow redon. reactions to proceed in a desired sequence in water. (15) Modern difference-density results from extremely careful Xray diffractionstudies reveal that the non-spherical and hence bonding electron concentration even between nuclei thought to be held by the strongest (multiple) bonds is, in fact, measured in small fractions of one electron. Likewise, lane-pair electron densities occupying coordination sites in compounds of the heavier elements are, in fact, merely fractions of one electron. (16) The role of entropy changes in determining the order of acid and base strengths in water is often decisive, but not appreciated. Thus, these effects are explained on bonding (internal energy) differences which are largely irrelevant. ~~
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Merhinks rhe Chymisui, in their searches after the truth, are not unlike the navigator6 of Solomon's Tarshish tleet, who brought home from their tedious voyages, not only gold, and siher and ivory, but apes and peacocks too: for so the writings of several of your hermetick philosophers present us, together with divers substantial and noble experiments, theories, which either like peacock feathers make a great show, but are neither solid nor useful, or else like aoes: if thev have some aooearance of beine rational. are blemish& iith some absurdity &'other, thar, when they are attentively ronsidered, make them appear ridiculous. Robert Boyle (162611-1691) in "The Sceptical Chemist"
It is true to sav that. in eeneral. in inoreanic chemistrv anything examined in & G e n t ddtail will-be found to d e anomalous. Even the vaunted periodic system of the ele-
ments does not work either verticallv or horizontallv as a reliable guide to the physical or chemical properties bf the elements or their com~ounds.There are many similarities between elements not E~ose~y related by the peiiodic system (orbital energy, ionic radius, soft and hard character, electronegativity, etc.). Aside from the more familiar diagonal relationships between Li and Mg (insoluble fluorides, high hydration energies, stable organomerallics), He and Al (strongly hydrolyzed in water), H and Si (dominant oxygen chemistrv). the similarities in behavior among- KT. . TI7..and Ag+ or d&, Mn2+, and Zn2+ are less systematic. In geochemistry A131 substitutes at mineral cation sites for Si4+, Fe3+ for AP+, Fez+ for Ca2+,and Ni2+for Mg2+.The classical n of Bunsen is also a p ~ a r e n t l v sulfide ~ r e c i ~ i t a t i oscheme unrelatfd tu period trends. In addition, the great t i h m p h if Mendeleev's breathrakine prediction of the discovery of eka-silicon (germanium) ;u;d the detailed properties of its compounds was accompanied by a now-forgotten claim that there would be an element found in the fifth main group between antimony and bismuth. Perhaps very fortunately inorgnnie chemistry dms not have one uniwmal well-order~ddedurrrva th~ury... . several complemmtary networks of concepts [canbe] used when rationalizing ehemical facts. . .chemistry is much more inductive than deductive, the facts are stubborn, and we do not yet know the surprise of tomorTOW.
Christian Klixbull J#rgensen
Memory 'It's a poor sort of memory that only works backwards,' the Queen remarked. Charles Lutwidge Dodson, Lewis Carroll (1832-1898)
It is more desirable to memorize facts instead of unconfirmed and quite possibly incomplete theories when the effort involved is the same. Russell S. Drago (192%) It is foolish t o give . . . the imprcsaion that chemistry is some sort of suh-lranrh of physics. 11 is nut. Chemistry has a torally difierent philosophy and has o srronalv creative putenrial. Ir mn create substances and materials never dreamt of before.
Jock Boldwin (193%
Students as a group are an accommodating lot and will give us what they perceive will please us. They will tell us that they have derived the structure of SF4 from first principles if that seems to be what we want, even if they have actually remembered its shape, instead. How healthier i t would be to take a leaf out of the books of our organic colleagues who unashamedly teach their students classes of compounds, reactions, physical properties, etc. Our catalog of descriptive facts is not only much larger than theirs (100 elements to one!) but also contains many more surprises and fascinating unexplained truths. Therein lies the intellectual challenge of chemistry. Not in oversimplified and hence incredible models, half-baked constructs and principles derived from irrelevant materials in the wrong phase, extrapolated beyond any reasonable point of usefulness. The descriptive facts are the permanent basis for our discipline, and their study should be restored to the central place i t deserves. A Program for Inorganic Chemistry
Facts are better than dreams.
in "Through the Lwking Glass"
Sir Winston Churchill in "The Gathering Starm"
Remembering is easy; the really hard thing to do is to forget. My undergraduate physical chemistry teacher a t the University of Pennsylvania, Robert E. Hughes, gave us an integer number between one and ten and asked us to try to forget it. Even after 30 years of trying, it has proved an impossible task. We have forgotten that everyone remembers evervthine. The - " I t is far easier than derivine- anvthine. " only question is, what to memorize? In our current mode of . n e d w o-w we ask our students to follow the path of memorizing
A Definition When Robert Townsend (1920- )took over the Avis Corporation, he first wrote a simple sentence describing what the company was in business for ("We rent cars without drivers"). The corresponding sentence for inorganic chemistry might be more wordy (Townsend was no pedant) and less simple. We offer: "Inorganic Chemistry treats the physical and chemical properties of the elements and their compounds in all phases and the application of these materials to technology." By chemical properties we mean both formation and transformation, synthesis and reactivity. By all phases we include the standard gas, liquid, and solid plus surfaces and colloidal states.
(1) the ground state, gas-phase electron configurations of the
atoms; (2) that electron promotion takes place;
(3) that hybridization of the atomic orbitals occurs; the shapes of the resulting hybrids; (5) the tenants of the Valence Shell Electron Pair Repulsion (VSEPR)model: and (6)that in trigonal-hipyramidal geometry the lone pairs of electrons go equatorial. (4)
From all this we are now ready to state that, for example, the SF4 molecule adopts a seesaw shape. Worse yet, a similar series of steps leads to the prediction that the binary group-IIA halides will be sp-hybridized and hence linear. However, most of the heavier examples are bent. This unpopular fact is seldom admitted. The alternative is simply t o memorize the seesaw shape of SF, and use the time saved to memorize the syntheses, physical properties, and reaction chemistry of SF4 and the other sulfur fluorides and halides, the oxyhalides and those of selenium and tellurium. This would have the merit of filling the heads of the students with immutable and interesting information which could help stimulate thought and wonder.
Drop the Name lnorganic Chemistry Inorganic is a negative word meaning lifeless, lacking vitality. There are probably better names available, but "Chemistry of the Elements" will do for now. Expunge All Names Chemistry is particularly plagued by the common use of non-descri~tivenames of . o e o.~ l ein d a c e of alternate. more explanatory terms. We have everything f n m Ahegg's rule, .4okin's catalyst. ?\dmiraltv brass. ALLADIN Proeram. - . Alfven number, t h e ~ m a d o riearrankement, i Andrussov oxidation, Angstrom unit, Archimedean antiprism, the Arbuzov reaction, the Arens-van Dorp synthesis, and several Arrhenius theories to the Zdanovskii law, Zeeman effect, Zincke cleavagr, and the %inin reducrion. Even well-practiced chemistscannot define these terms precisely except for their own areas of specialty, and no single nource exists to serve as a lexiron. In addition we have over one hundred elements which themselves lack svstematic names lbut see Pure ADD!. Chem. 1973.51, 3811. ~ e r c i f u l l yinorgahc , compounds'& now be named systematically, but there are still many Volume 63 Number 10 October 1986
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choices. Often the attempt to honor the already famous chemist is misplaced (cf. Matthew 2529 "For unto evervone ~~~that hath shafi he given, and he shall have abundance: hut from him that hath not shall be taken awav even that which he hath."). Moreover, each national a n i language group tends to remember its own, and so the names are not transferrable geographically, and they change with time as friends of the honoree pass on. Most choices of names are hased upon atrocious historical scholarship or none a t all. As one wag ohserved, "The only thing sou know when vou find something named after s6meoni is that he did not do it!" An obvious improvement will he wrought in freedom from ohscurity and obfuscation and, especially, ease of access to information by the outsider and student.
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Fall Out of Love with Spectroscopy
Excellent! I [Watson]cried. Elementary, said he [Holmes]. Sir Arthur Conan Doyle in "The Crooked Man" I t is time that we end our long affair with spectroscopy and return home to our f i s t love, chemistry. Current inorganic chemistry research is spectroscopy-driven, hut much of spectroscopy's role is in helping to guess structure. Modern developments in X-ray crystallography and expanded access to diffractometer obviates this need. Moreover, distracting the attention of the chemist from the chemistry of the svstem to the physics underlying the spectroscopic~methodhas misdirected much effort and talent into matters not central to the mission of the chemist. Moreover. much data that real spectroscopists would call poor have been collected. I t is a sad fact that, in ~eneral.anv two independent soectrosco~ic measurements will deviate butside thk assigned experimental error of one another.
meaningless. It's only the interpretation we give those fads which counts. Earl Stanley Gardner in "The Case of the Perjured Parrot" Our principles and models provide, inter alia, a nomenclature and system of classification. Despite all its failings, the periodic system provides these services and is a useful and perhaps essential device for organizing the descriptive chemistry. Such aids are not to he despised. The names of period groups should he decided upon and quickly brought into universal use. A New Freshman Chemistry Textbook A new textbook must be written reflecting the new realities, one that is readable and can be easily taught from, one that reveals the fascination of our descrintive science. It is a truism that even inorganic chemists themselves do not know the descriptive chemistry the students need. The author of the new textbook can use the descriptive portions of the advanced inorganic texts now available nlus series such as "~omprehens6eInorganic Chemistry" erga am on), "Gmelins Handbook of Inorganic Chemistry" (Springer Verlag), "Inorganic Reactions and Methods" (VCH) a t the research level to bring together a central hodv of information eenerally agreed to be of greatest importance and interest, &d then to organize this information in a digestible form. Retwn the Laboratory to the Teaching of Skills
The things that any arienep discovers are beyond the reach of direct observation. We cannot see energy, nor the attraction of grat,itntion,nor the flying moleeulesofgasesnor the lurniniferous ether, nor the forests of the carbonaceous era, nor the explosions of nerve cells. It is only the premises of science, not its conclusions, which are directly observed. Charles Sanders Peirce (1839-1914)
Allow the Proper Study of Chemical Reactions to Reemerge
You know my method [said Holmes]. It is founded upon the observance of trifles. Sir Arthur Comn Doyle in "The Boscombe Valley Mystery" We need good, tested recipes. Chemical reactions should be characterized by yield, mass balance, effect of temperature, pressure and catalysts, need for special apparatus and techniques, selectivity, utility, economy of starting materials, ease of isolation and purification of products, rate, activation parameters, stability of products toward air, moisture and heat, presence of intermediates. the existence of eouilihrium, etc.- he collection of reprodkcihle preparation's is a t the core of the archive of chemistry. Restore Technical ChemislN to a Piece of Honor The modem equivalents of depictions of blast furnaces, the way in which sulfur is mined from the earth, etc., should win an expanded place in freshman chemistry textbooks, and the processes they describe should he reintroduced into the main body of the curriculum. The student revolution of the 1960's had as one consequence the generation of much had press for the chemical industry and the driving out of technical chemistry from the curriculum. I t is time now to reverse this trend and t o allow the latest technical achievements to reemerge in a thoroughly modern way. We Need Gwd Mnemonics, Not More Weak Theorems
That's the worst of circumstantialevidence [said Perry Mason]. The prosecuting attorney has at his command all the facilities of organized investigation. He uncovers facts. He selects only those which, in his opinion, are significant. Once he's come ta the conclusion the defendant is guilty, the only facts he considers significant are those which point to the guilt of the defendant. That's why circumstantial evidence is such a Liar. Facts themselves are 832
Journal of Chemical Education
Laboratory teaching a t the first-year level needs to be converted from the exercises attempting to demonstrate principles it is now (impossible) t o a series of exercises in learning to synthesize chemicals, isolate and purify the products, and determine just what has been made in what yield (possible). This should be coupled with the old Bunsen oualiiative analysis scheme or its-modern equivalent and dther exercises involving unknowns, which always heighten student interest. Rewards (grades) should he hased upon testable lahoratory parameters such as yield and purity of product rather than the quality of reports usually copied from fraternity- or sorority-house files. The ahility t o name the pieces of apparatus and the discipline developing in perfmning the experimental manipulations will he permanent and valuahle additions to the students' skills. Win Back the Second Semester of General Chemistry for Teaching Descriptive Material
Just the fa&, Ma'am. Jack Webb as Sgt.Joe Friday on "Dragnet", NBC Television The conventional response of inorganic chemists to the call for curricular reform, for example, by the Committee on Professional Training of the American Chemical Society, is to offer to teach an additional semester of work after the freshman year. From the adoptions patterns of the currently availahle textbooks for this one-semester course, it is ohvious that the material being presented is hased heavily upon nominal principles rather than facts. In anv case. relegating basic inorganic chemistry to a position outside the general course is not satisfactory for many reasons. The real answer lies in recapturing the second semester of the general chemistry year for the teaching of the descriptive
chemistry of the elements and their compounds. Students from outside chemistry would then he exposed t o this material which they now miss by taking only one year of chemistry. The inorganic staff for the freshman chemistry program, hich a t most institutions shares about half the load, would hen be able to concentrate their efforts on the second part. Enough of the basic atomic physics and bonding concepts would have been covered in the first semester so that the students would now be ready for a tour of the facts, most likely organized around the framework of the periodic table. Current textbooks for the general course would need to be augmented by additional supplementary reading material covering descriptive facts, or by one of the already available one-semester basic inorganic texts which emphasizes descriptive chemistry until the day when a single general chemistry textbook which fits such a bifurcated course as described here will be published [see the section above entitled "A New Freshman Chemistry Textbook."] A further consequence of such a plan, apart from assuring a larger academic employment base for the inorganic discipline by recapturingjohs now lost to the physicalandanalytical divisions of departments, will be to bring together into a more cohesive group the inorganic staffs which will be required t o reorganize and refocus their efforts in order t o carry out their new responsibilities in the freshman curriculum. The relearning of the descriptive material will have the further effect of stimulating lines of research which will be driven by the engine of fact and result rather than theory and cause.
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Goals
Now what I want is Facts. Teach these hays and girls nothing but fads. Facts alone are wanted in life. Plant nothing else, and root out everything else. You can only form the minds of reasoning animals upon Facts; nothing else will even be of service to them. This is the prineiple on which1bring upmy own children, and this is the principle on which I bring up these children. Stick to Facts, Sir!. . . The speaker and the schoolmaster,and the third grown person present, all hacked a little, and swept with their eyes the inclined plane of little vessels then and there arranged in order, ready to have imperial gallons of facts poured into them until they were full to the hrim. Charles Dickens (1812-1810)in "Hard Times"
We aim for a rebirth of descriptive chemistry and its broadest possible exposure to the students. Relearning descriptive chemistry will excite the teachers' interest and hrine out their hest nedaeow. From amone the students they teach will come the next generation of inorganic chemists alreadv knowine the facts which thev need to advance the discipline. By descriptive chemistry we mean syntheses, reactions, and commercial processes, physical properties, phases a t various tem~eraturesand messures. structures, habits and solubility behaviors that we can see, smell, touch and even hear. This is material that is eminently memorable. Indeed, this is the stuff the students remember a11 of their lives and whose immediacy can capture their imaginations.
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