The grim silence of facts

Now we all have our off days (does not t.he very ... books were going to start by defining electrophilicity and nucleophilicity and then go on to dedu...
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w w nue graumg a oeglnnlng grauuaze Inorganic examination some time ago I was startled to discover that the student believed silver chloride to be a pale green gas. Now we all have our off days (does not t.he very first sentence of chapter one of a recent, and excellent, paperback run: "A flammable silver metal seizes electrons from a deadly green gas, and the resultant positive and negative ions line up into the tasty crystals of common salt, NaCI"?),, and I read on willing to forgive and forget, if not to allow partial credit. A little later the student launched into a long, plausible explanation as to why silver chloride is a . pale areen aas. I w;ts reminded of Dr. Johnson'ss: "I can give youthe explanation, M'am, but not the understanding of it." At a subsequent ACS meeting I Imentioned the incident to some colleagues and one of t hem remarked, "what a pity he got the theory wrong," an attitude which in some ways disturbed me more than the thought of a greenly gaseous silver chloride. There is little doubt that the li st ten or so years have witnessed a steady discounting of facts, particularly inorganic facts, in the teaching of undergraduate chem~ - ..-L L . ~ ~ . ~ ~- ~ ~ ,or,istry. I am not speaking of any parclcular oouy facts-for none merits universal attention save that Pobbles are happier without their toes-but rather of that meagre covering of factual flesh on the theoretical skeletons which fill our chemical closets. The skull beneath the skin is indeed fundamental but to anyone hut a theoretician scarcely a matter of infinite zest. As an apostate I must reluctantly confess that they order these matters much better in organic chemistry than they do in my adopted faith of inorganic.. There was a moment of danger when it looked as if the textbooks were going to start by defining electrophilicity and nucleophilicity and then go on to deduce the facts of organic life from these. But with his natural gift for creative' reaction the organic chemist resisted the temptation and the danger passed. Present organic texts, even the so-called "sophisticated" ones, seem a wise blend of current fact and current fancy. The agony of the catalog of name-reactions has been mitigatedbycor ' ' ' " gh the tedium may ;h factual message Would that w e u u u l u say u m aama ul I I I W ~ ~ U L Cchem: istry! It is now about ten years since a one-semester inorganic course was made mandatory in ACS approved curricula and a compelling case could be made that today's graduates know much less factual inorganic chemistry than they did before the requirement was put in. Freshman chemistry insists on principles even 1~

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cuougn, roc a variety of reasons, both feet are frequently planted firmly in mid-air.' Qualitative analysis has gone, unmourned by the operationally-amplified analytical chemist though missed by a few sentimental inorganic chemists, and in its place we too often have "sloppy quantl'-a phenomenon, like partial virginity, of dubious worth. And so the student arrives at his inorganic course almost totally innocent of inorganic fact. For all he has been told silver chloride might very well be a pale green gas. What then do we do with him in the forty odd lectures a t our disposal? Judging by the responses of some 200 entering graduate students over the last few years the typical senior inorganic course leans heavily to theory, particularly to bonding theory. Since so many of their teachers are children of the fabled Rennaissance of Inorganic Chemistry (surely reports of its implied death were greatly exaggerated?) this is not surprising but even in our own narrow interest-to say nothing of that of students who do not happen to go on to graduate work in inorganic chemistry-is it wise? That we should begin by setting up a skeleton of in~ organic principles is undeniable. Without it the presentation of facts becomes inefficientand their accumulation a shapeless mass of protoplasm. But these principles should not be restricted to the narrowly structural. Instability and stability, lability and inertness, oxidation and reduction, acidity and basicity, and their relationship to position in the periodic table are as much a part of modern inorganic chemistry as is ligand field theory, though admittedly they are less fashionable. A beginning graduate student may be forgiven for not knowing the catalytic niceties of the preparation of sodium amide but not for suggesting that sodium be dropped into aqueous ammonia. He should be faulted as readily for hazarding that SiD4 be made from SiOz and DzO as for ascribing a chlorine-bridge structure to SizCIB. He should even know that silver chloride is a white solid largely insoluble in water and in a general way he should know why. But, the arguments run, teaching the facts of inorganic chemistry is dull beyond conception. Leaving aside the implicit suggestion that molecular orbital theory is intrinsically hilarious, one must demur. Anyone who can bring life to a character table should not despair of lending a little color to the oxidation states of vanadium. I t takes effort-what in teaching doesn't-but the effort must be made. For as Conrad urged: "Every sort of shouting is a transitory thing, after which the grim silence of facts remains." Derek A. Davenport

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D., ''Elevate Them Guns a Little Lower," J.

.,45, 419 (1968).

Purdue University Lafoyette, Indiana 47907

17,Number 4, April 1970 / 271