Vol. 7 ;
D. FREDRICKSCIS lowering the wave height the wave is split into two waves (polarogram D, Fig. 2 ) . Interpretation of his behavior is difficult and complicated b y the proximity of the wave to the discharge of the supporting electrolyte. The possibility that this wave is similar to the anomalous wave often found in solutions of high ionic strength'? is ruled out since dilution of the buffer does not change its height. T h e wave is likewise not caused by hydrogen ion depletion a t the t l 2 ) I.
AIeiteb, THISJ O C R S U . ,
electrode surface as suggested by Ruetschi antl Trumpler, '" since the wave height remains lairlp constant with the change in pH. This independence with changes in QH and the low diffusion current constants eliminates the possibility t h a t this wave represents further reduction of these compounds to aniline. 8~1:H k' I < n c . t ~ c i i i~
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The Polarographic Behavior of an Equimolar Mixture of Azoxybenzene and Hydrazobenzene BY S.WAWZONEK A N D J. D. FREDRICKSON' KEcrrvEn
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17, 19.5.;
The polarographic behai\-iorof :in equiinular inisturc: of azoxylieiizene antl hytlr;~zoheiize~ic hits been foutld t o be different from t h a t of ci:-azobenzeiic iii :t pII range of 2.0 to 11.1. These results are in agreement with data obtained b y others Froiii rption spectra qtudici, therin;tl tlxta, X-ray studie.: and dipole moments, which confirm the structure of cis-azobenzeiic geometrical isomer and not as :L double compomid of azouybenzenc and hydrazobenzene. T h e polarographic re.;tilt\ likewise show t h a t no iiiteraction occiirs between azouylwrizcne and hydrazohenzene in the buffer range 2.0 t o 11 1 .
T h e postulation t h a t cis-azobenzene is not a geometrical isomer of trans-azobenzene b u t a double compound of azoxyhenzene and hydrazohenzene? has been disproved recently by absorption spectra ~ t u d i e sthermal ,~ data and X-ray studies.'& The polarographic beha\-ior of an eyuiniolar mixture of azoxphenzene and liydrazobenzene Iixs i l o \ V heen studied, using acilleolls niethannl :IS a solvent arid buffers ranging from PH 2.0 to I 1 . 1 , and coinpared with that of the pure corripoiielits and of ris-:tzohenzelic. Such an investigation \IWS considered to be of iritcrcst in that not only would i t study the s?-stcni under different conditiolls iroiii those used by thc other physical methods, l)ut it would also determine whether any interaction occurred between the two compounds under the influence of acids or bases t o produce cis- or f r o m ambenzene.
was used as a maximum suppressor and n-as oht:iined from Eastmtn Kodnk Co.
Results The polarographic behavior of azoxyhenzene i n .jOycisopropyl alcohol and .?Or; methanol is given in Tables I 2nd 11. T n avoid maxima the conceiitration of azoxybenzene in 30c; niethaiiol was krpt hclun. O..i ~iiilliinolar.
,.I.\BLIS PROFTI,
Ai.ccii~or.AT
A
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*?0% IS(>Coxcr$xnof the linear partial hydrolysis products, ~ t @ / C K r ( E t O ) S i O j , , Ewith t, minor atnotints of the cyc!ic Iroducts, ICHr(I?‘tO)SiO]., ivhere n is 3 t o 5. Under certairi conditions, it is possible to isolate sinal! amounts of sub1iin:ible solids having the composition, ( CI-12Si0,.5),,,where n is proh ably 6 and 8.
Introduction Trifunctional silanes of general structure RSiX3, \\,here R is an alkyl or aryl group and x is a functional group such as halogen, alkoxy or acyloxy, produce cross-linked polymeric structures LVhen hydrolyzed. Among organic silicon products, these structures are at present least well understood. Tile characterization of partial hydrolysis prod.. ucts of trifunctional silanes tvas unc1ertal
