Sulphuric Acid and Related Compounds

Sulphuric Acid and Related Compounds. The vibrational spectra of H2SO4 and D2SO4 in the crystalline state have been measured at various temperatures. The cation-transference numbers of Li, Na, K, NH3, Ag, and Ba hydrogen sulphates, and of solutions of water and acetic acid, have been measured in 100% H2SO4 at 25 °C. The numbers obtained were of the order of 0.005, much smaller than was previously believed. The behaviour of hafnium dioxide and copper(ii) oxide in sulphuric acid has been studied and various compounds have been isolated. 

S04 was obtained, and it was suggested that electrochemical and spectro-photometric measurements of the dissociation constant of HSO4 should take into account the presence of such ion pairs. 

Compounds with the composition Ti(MeS03) Cl4 (n= 1—4) have been prepared by the action of methanesulphonic acid on titanium(iv) chloride. 

The crystal structure of trifluoromethanesulphonic acid hemihydrate has been determined.The structure consists of ions, CF3SO3 ions, and CF3SO3H 

Sulphides.—Since many of the sulphides treated in this section will have been dealt with in detail elsewhere in this volume, only features of interest will be 

Sulphuric Add and Related Compounds.—A comprehensive review (883 references) of the analytical methods available for the inorganic acids derived from sulphur has been published.193 Data on i.r. absorption spectra have been used194 to determine the equilibrium concentrations of undissociated sulphuric acid in aqueous solutions of concentration 99.7—82.6 mass % H2S04. Considerable quantities of the undissociated acid were found to be present in the equimolar and more dilute solutions. It has been established195 that thionyl chloride reacts with sulphuric acid with the formation of chlorosulphonic acid. The kinetics of the reaction, which is of order 0.5 with respect to sulphuric acid, were also studied. The density, 

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Formation of phenolic esters with sulphuric acid and related compounds... 

The use of cryoscopic measurements for the determination of activity coefficients in aprotic solvents has been very limited, although much information is available on the evaluation of molecular weights and studies of solvent association. Relative to protic solvents more information is available and the investigations of Gillespie and coworkers in sulphuric acid and related compounds have been compiled to indicate the general scope of this technique in protic solvents. The information is presented in alphabetical order by solvent. 

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