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I JOHN K. TAYLOR, National Bureau of Standards, Washington, D. C. Styrene ... nichrome wire. asbestos, plaster of paris, and appropriate ac- cessory m...
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CHEMICAL PROJ Research Ideas for Young Chemists JAY A. YOUNG, King's College, Wilkes-Barre, Penna. JOHN K. TAYLOR, National Bureau of Standards, Washington, D. C.

Styrene lodochloride See BLCKLES, R E

, AND KNAACK, D. F , J. Chem Educ , 37, 298-301 (1960) Questions: Determine the structure of the compound that forms when iodine monochloride is added to styrene. Show t,hat Markovnikov's rule is, or is not, obeyed in another addition reaction which you select for study. Can the principles used here, and other similar principles, he used to determine the structure of an organic compound which you select for this purpose?

Styrene iodochloride can be prepared by the addition of iodine monochloride to styreno, a reaction that proceeds readily, although an excess of iodine which can result is somewhat troublesome to remove. Either of two isomers could form, 1-chloro-2iodo-1-pheiiylelhane or I-iodo-2-chloro-1-phenylethane,as the major product. Dehydrohalogenation of the product followed by hydration, with identification of the products of these reactions, load to the conclusion that the vicinal dihalide that is formed is the I-chloro-2-iodo isomer. Procedural details for the preparation of the dihalide and for the reactions which lead to the proof of its structure are given,

Simplified Laboratory Apparatus for Vapor Phase Catalytic Studies See W E N D L A ~R D ,, J Chem E d u c , 21, 171-4 (1944)

Catalytic processes play an important role in the manufacture A study of catalysis ai adapted to polymerization, cracking, alkylation, cyclization, oxidation, or any other type of reaction, would be particularly interesting to a student who hopes t o become a chemical engineer. The apparatus described and the procedures suggested in this article are designed to encourage an interest in chemical engineering. By means of ii simple pump, a liquid or mixture of liquids is passed at a measured constant rate into a furnace, where it is vaporized. The vapor passes into a second region in the same furnace, where it. comes in contact with a selected catalyst. The products of the reaction arc collected in a suitable container and analyzed to determine the nature and extent of the reaction. Wendland suggests that commercially available furnaces he used; if necessary, the furnaces could be constructed from nichrome wire. asbestos, plaster of paris, and appropriate accessory materials. Some parts of the pump described in Figure 3 will he difficult for the beginner to make, and probalbly should of many chcmical products.

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he constructed by a skilled glass blower; the cost will not be excessive. A large tube, calibrated with wax pencil marking, or ink marks on a gummed paper strip, can be substituted for the graduate cylinder shown in Figure 3 of the article. Questions: Can you make a gasoline from household heating fuel oil which would be suitable for use in a small (model airplane type) engine? How many different olefins can you make from various kinds of alcohols? Why is it necessary to regenerate a catalyst after it has been used for several hours? Can you prepare phthalic anhydride from naphthalene? Select a suitable liquid or liquid mixture, and a suitable catalyst, and determine the effect of one or both of the following variables on the nature and yield of the products formed: the temperature of the reaction; the contact tim'e of the reactants with the catalyst. Account. for the results you obtain.

Experiments with cyclopentadiene See WACNEB,E C , A N D HUNT,W C , J Chem. Educ, 28,309-11 (1951) upon the temperature, using a hygrometer or dilatometer which Cyclopcntadiene, like other conjugated dienes, will undergo you have constructed. Can you plot the data you obtain on a many react,ions and exhibit interesting properties. Several of graph in such a way that the functions you plot are linearly these-dimerimtion, the formation of the monomer from the related to each other? dimer, extensive polymerization, a Diels-Alder reaction, and a The article states that both the monomeric and dimeric forms condensation-are described and the procedures for each are of this diene will polymerize in the presence of concentrated sulexplained in this article. furic acid. Are there any other Br0nsted acids which will induce Students who wish to learn about the details and complexities polymerization? Will some Lewis acids induce polymerization? of organic reactions will profit from the experimental studies deIf so,. suggest reasons why, and test your explanation by further scribed by Wagner and Hunt. The procedures described can laboratory work. he carried out in a few hours; after this introductory study, Will cyclopentadiene undergo a Diels-Alder reaction with interested students might wish to pursue the matter further. any other compounds, in addition to maleic anhydride? investigating other reactions of cyclopentadiene and its dimer, Can you prepare any other derivatives of fulvene, in addition and similar reactions of related compounds. to diphenylfulvene? By a laboratory study of the reactions of other conjugated Questions: dienes, show that their properties are, in some cases, similar to the properties of cyclopentadiene Show that the rate of dimerimtion of cyclopentadiene depends ~~

Volume 39, Number 2, February 1962

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