Ionic Liquids Research Paper

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2.1 Introduction to Ionic Liquids Ionic liquids (ILs) are liquids composed entirely of organic cations and inorganic or organic anions. Those systems that are liquids at high temperatures for example NaCl with melting point at ≈ 800 0C is normally termed as molten salts, on the other hand room-temperature ILs are liquids below 100˚C that have received considerable attention as substitutes for volatile organic solvents. Owing to their fascinating properties, such as negligible vapour pressure, large liquidous range, high thermal stability, good ionic conductivity, high electrochemical stability, they are considered favourable solvents for chemical syntheses. ILs are also called as designer solvents because their physical and chemical properties…show more content…
Liquids with lower viscocity flow more readily.In general ILs are more viscous than molecular solvents. The viscosities of ILs at room temperature typically lie in the range of 10 to 500 cP [6]. For example, the viscocities of and at 25 0C are 34 and 270 cP, respectively. The viscosities of ILs generally increase with increasing size of the cation, and particularly with increasing alkyl chain length. For example, the viscosities of and at 25 0C are 167 and 202 cP, respectively. It is observed that the viscosity of ILs increases by selectively changing cation and anions that can be attributed to increase in van der Waals forces [main10] for example, in the 3-alkyl-1-methylimidazolium hexafluorophosphate ([Rmim] [PF6]) and bis(triflyl)imide series ([Rmim][Tf2N]), viscosity increases as the number of carbon atoms in the linear alkyl group, is increased [25b]. The symmetry of inorganic anions also affects the viscosity of ILs to the considerable extent and the viscosity decreases in the order > > > [25]. ---------added physicochemical propertie from main_reference---- [10] Xu W, Wang L-M, Nieman RA, Angell CA. J. Phys. Chem. B 2003; 107:

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