Graphite bisulfate

MeO)3CH, anhydrous MeOH, TsOH, reflux, 2 h. Diethyl ketals have been prepared under similar conditions (EtOH, TsOH, 0-23°, 15 min-6 h, 80-95% yield) in the presence of molecular sieves to shift the equilibrium by adsorbing water. Amberlyst-15 or graphite bisulfate and (EtO)3CH have been used to prepare diethyl ketals. 

Graphite bisulfates are formed by heating graphite with a mixture of sulfuric and nitric acids. In the reaction, the graphite planes are partially oxidized. There is approximately one positive charge for every 24 carbon atoms, and the HS04 anions are distributed between the planes, (a) What effect is this oxidation likely to have on the electrical conductivity (b) What effect would you expect it to have on the x-ray diffraction pattern observed for this material Refer to Major Technique 3 on x-ray diffraction, which follows this set of exercises. 

Thermodynamic information has been obtained in different stages of graphite bisulfate (A5). The results have been interpreted in terms of a model previously applied to alkali-metal-graphite compounds. Part of... 

Graphite bisulfate prepared from commercial graphite. .. 46... 

These results may be interpreted on the basis of the band model for graphite J 9, 88). Because of the loss of electrons during the oxidation, holes are produced in the low er almost eompletely occupied band of graphite and as a result the number of charge carriers increases. Since this occurs predominantly in the lower band, the Hall constant is positive. Graphite bisulfate is thus a conductor of the p-type. 

Yaroshenko A.P., Savoskin M.V., Magasinski A.N., Savsunenko O.B. Synthesis and thermal expanding of residual graphite bisulfates produced in Na2Cr20v-H2S04 system. 

H2SO4/ROH ROH, H2SO4, HC(0R)3 ROH, supported H2SO4 ROH, MeSOjH ROH, TsOH ROH, graphite bisulfate ArOH, B(0H)3, H2SO4 ROH, BFj OEti... 

ESTERIFICATION 6-ChIoro-l-p-chIorobenzenesuIfonyIoxybenzotriazole. Graphite bisulfate. Hexamethylphosphoric triamide. l-Methyl-2-bromopyridinium iodide. Tri-phenylphosphine ditriflate. Hexamethylphosphoric triamide. 

Properties and structure correspond to those of graphite bisulfate. 

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