Single-ion transfer energetics of some ions based on TATB assumption in aqueous mixtures of N,N-dimethylformamide

Abstract

Single-ion transfer energies <img src='/image/spc_char/delta.gif' border=0><i>G</i><img src='http://www.niscair.res.in/jinfo/equation30.gif' border=0>(i) and entropies <img src='/image/spc_char/delta.gif' border=0><i>S</i><img src='http://www.niscair.res.in/jinfo/equation30.gif' border=0>(i) of some electrolytes from water to 20, 40, 60 and 80 wt % aqueous N,N-dimethylformamide (DMF) solvents have been determined at 25°C using the widely used tetraphenylarsonium tetraphenylborate (Ph₄AsPh₄B, TATB) reference electrolyte (RE) assumption from solubility and emf measurements at five temperatures in the range 15-35°C.Analysis of <img src='/image/spc_char/delta.gif' border=0>G<img src='http://www.niscair.res.in/jinfo/equation30.gif' border=0>(i) values of the ions as well as the chemical effects, <img src='/image/spc_char/delta.gif' border=0>G<img src='http://www.niscair.res.in/jinfo/equation30.gif' border=0>, _ch(i), as obtained after correcting for the cavity effects, <img src='/image/spc_char/delta.gif' border=0>G<img src='http://www.niscair.res.in/jinfo/equation30.gif' border=0>, _cav(i), estimated by the scaled particle theory (SPT) and the Born as well as ion-dipole type electrostatic effects, estimated by use of simple Born and Kim formulations respectively, reveals that cationophilicity, aninophobicity and/or predominant dispersion interactions of the solvent mixtures are guiding the solvation behaviour of the ions. But the corresponding T<img src='/image/spc_char/delta.gif' border=0><i>S</i>(i) values obtained after due correction of the cavity and Born-type electrostatic effects from T<img src='/image/spc_char/delta.gif' border=0><i>S</i><img src='http://www.niscair.res.in/jinfo/equation30.gif' border=0>,_ch(i) values, reveal the mirror image entropic behaviour of simple cations and anions that can be explained in the light of Kundu <i>et</i><i>al</i>.'s four-step transfer process.