edited by: JOHNJ. ALEXANDER University of Cincinnati Cincinnati.Ohio 45221
exom quwtion exchange Empathy for the Exile: Chemistry and Classical Literature A. C. Tanner and J. F. Johnson Austin CDllege Sherman. TX 75091 Novel problems in physical chemistry can stimulate student interest once students have mascered more routine skills. Also it is in the soirit of the liberal arts to find oroblems that touch on several disciplines. As an example oisuch a novel. interdisciolinarv- nroblem we offer the followine. . -. which involves chemistry, classical literature, and history of science. Problem In 8 A.D. Aurmstus Caesar exiled the Roman noet Ovid to the remote ~ l k Sea k town of Tomis (moderd Constants, Romania). Not only was Ovid isolated from the political, social, and intellectual center of his world, but also he had to endure a climate much harsher than that of Rome. T o iament his exile, he wrote the Tristia ( I ) , poems that detail his ohvsical and emotional discomforts. in . particular in Tristia I1f10 he writes: nudoque consistunt, formam servantia testae, uina, nec hausta meri, sed data frusta bibunt. [and the wines stand stiff, jugleas but keeping the shape of their jugs, and the people don't drink draughts ofwine-they eat pieces of it.] Cold indeed, but exactly how cold? Our modern temperaturescales trace back only t o the 17thand 18thcenturies (2), so there are no temperature records from Ovid's time. However, chemists will immediately recognize tbat the phenomenon of the freezine-ooint denression (3) can he aoolied t o estimate the free& point df the wine,'provided b i course that the com~ositionof the wine can be estimated. At this point classical scholarship (4) is crucial since there were different Latin words for the different kinds of wine consumed a t the time, including wine diluted with water. But in fact "uina" and "meri" do mean undiluted mape wine, as might have been assumed. Estimate the temp&ature suffered by O n d and state any assumptions necessary or convenient. Acceptable Solutlon I t is simplest t o assume a composition for the wine comparable to that of modern grape wine. But well over 200 constituents are given in Kirk-Othmer (5).Recognize that only an estimate is desired or even justified and thus only the major components (water and ethanol) need be considered; the rough composition is water 87% and ethanol 13% by volume. The solution may be assumed ideal and dilute so that the expression (3) ~~~~~
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Journal of Chemical Education
can be used to obtain a freezing-point depression of -5 K, which corresoonds to a freezine noint of about 23 OF. The average ~ a n ; a q temperature :;modern C o n s t a m is between 14 and 32 OF (6).so the estimate seems reasonable. I t is quite likely that 0;id suffered even lower temperatures for orolonced periods since the wine in the storace vessels w & a p p a r k G frozen throughout. Note that the average January temperature in modern Rome is 41 O F , which fact supports Ovid's claims of physical hardship. The problem can also he studied by experiment and thus the assumption of an ideal dilute solution can be examined. Experlmental The material for study [Cabemet Sauvignon, Robert Mondavi Winery, 19851was purchased from a local supplier and used without further treatment. The freezing point of the wine was determined by a well-established procedure (7).In view of the limited precision needed, an ordinary thermometer replaced the differential therand mometer tv~icsllv -. " used in such exoerirnents.A bath of table salt -~~~~~ a tao-water ice was used to cool the wine. It was ohserved that ~~..-.the .... wine contained particulate matter; probably as a consequence of that fact, a sharp freezing point was not observed. Rather a slush began to form about -6.5 T , and the temperature fellvery slowly to about -7.5 'C. ~~~~
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Results and Dlscusslon Because of oarticulate matter in the wine. a com~arisonof the observed freezing range with the prediction of kq 1is not iustified. The wine could have been filtered. but it seems more appropriate simply to accept the experimental result as it stands since it is quite possible Ovid observed wine that also contained particdate-matter. Thus, from the experiment i t seems reasonable t o take -10 'C as a rough estimate of the cold experienced by Ovid, since be observed wine tbat was frozen solid and not a slush. On the Farenheit scale that temperature is about 15 O F , which accords with the lower average temperature in modern Romania. Acknowledgment We would like to thank Pamela Duke for a helpful discussion. Literature Cned
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