Study On The Physicochemical Properties Of The Aqueous Solutions Of The [C_nmim][OAc](n=2,3)

Ionic liquids are composed entirely by positive and negative ions. Recently,however, throughout the world nowadays, there have been an apparent new trend that,by the vapor pressure statistics currently available, it could be seen that the value ofthe vapor pressure of the ionic liquids are lower than that of the normal liquid phase,and that a wide range of chemical reactions can actually be performed in them.As an epoch-making kind of "brand-new generation" solvent which is extremelygreener and much more environmentally friendly, the carboxylic acid series of ionicliquids have attracted more and more attentions from both industrial fields andtheoretical-and-technological research fields, and thus they are specialized andcharacterized mainly by the viewpoint of green, toxic free, pollution-free anddesignable functions. Among this paper we utilize the Acetic Acid Ionic Liquids（[C_nmim][OAc]（n=2,3）） as the target substances of the research, using itsthermodynamic properties among the entire physicochemical properties as themainframe elements of the research, and the following research work has been done:By using the neutralization process, we have accomplished the tasks which arethe syntheses of two Acetic Acid Ionic Liquids （[C_nmim][OAc]（n=2,3））[C₂mim][OAc],1-ethyl-3-methylimidazolium acetic （[C₂mim][OAc]）,1-propyl-3-methylimidazolium acetic（[C₃mim][OAc]）, and through utilizing the1H NMR andthe Differential Scanning Calorimetry （DSC） and other modernised analyticalapparattuses, they have been characterized.The values of density and surface tension of aqueous [C₂mim][OAc] and [C₃mim][OAc] with the molality ranging from0.0002to0.0090mol·kg-1were determined inthe temperature range of （288.15to328.15） K, while every5K in each, and theexperimental values of the parachor for these solutions were calculated. Using theempirical equation of the parachor, the surface tension of these aqueous solutions wasestimated, and the estimated values are in good agreement with the experimentalvalues within error, and it turned out to be quite reasonable.These estimate values, could be deemed to have vital impact to the in-depth researches of the ionic liquids mentioned above, also, to the solution chemistry.