Solvent conductivity

A substance which, in the molten state or dissolved in a suitable solvent, conducts electricity and is simultaneously decomposed by it. 

The Triphenylmethyl Ion.—A solution of triphenylchloromethane in a dissociating solvent conducts the electric current (Walden). Since, on electrolysis, triphenylmethyl is liberated at the cathode, it follows... 

Conductivity, Electrical Conductometry and Conductometric Titrations. Electrical conductivity is thequality or ability of a substance to transmit electrical energy. If it deals with the conductivity of an electrolyte in solution, it is then called electrolytic conductivity. Conductometry deals with analyses by measuring electrolytic conductivity, based on the fact that ionic substances in many solvents conduct electricity. Conductometric titrations are quantative analysis based on the fact that with the addn of the titrating agent to a soln being titrated, the specific conductivity (reciprocal of specific resistance in mhos) changes at a different rate before and after the end point (Comp with Potentiometric Analysis) Refs 1 )Kirk Othmer 4 (L 949), 325-33 (Conductometry) 2)W.G.Berl, Edit, "Physical Methods... 

Yields refer to pure, isolated products. Dichloro-methane was employed as the solvent. Conducted at 70 C for 2 h by using 2.0 cquiv of EtjN. Conducted at 70 C for 1 h. 

Preparation of Solvent Conductance Water.—Distilled water is a poor conductor of electricity, but owing to the presence of impurities such as ammonia, carbon dioxide and traces of dissolved substances derived from containing vessels, air and dust, it has a conductance sufficiently large to have an appreciable effect on the results in accurate work. This source of error is of greatest importance with dilute solutions or weak electrolytes, because the conductance of the water is then of the same order as that of the electrolyte itself. If the conductance of the solvent were merely superimposed on that of the electrolyte the correction would be a comparatively simple matter. The conductance of the electrolyte would then be obtained by subtracting that of the solvent from the total this is possible, however, for a limited number of solutes. In most cases the impurities in the water can influence the ionization of the electrolyte, or vice versa, or chemical reaction may occur, and the observed conductance of the solution is not the sum of the values of the constituents. It is desirable, therefore, to use water which is as free as possible from impurities such water is called conductance water, or conductivity water. 

The membrane conductivity of Nafion in various protic solvents has been measured in a recent study and the results are given in Table 12. The ratio of the membrane conductivity (k) to the solvent conductivity (k ) is listed in the last column of the table. A plot of the conductivity ratio (/solubility parameter of the solvent is shown in Fig. 22. The membrane conductivity is higher than the solvent conductivity in all solvents except formamide. 

The same type of methodology was also used to prepare ferrocene-containing arylidene polyesters 122 in good yields from dicarboxyl ferrocenes and organic diols. These materials were characterized by elemental analysis, IR spectroscopy, viscometry, and WAXS. The polymers were found to be semicrystalline but were soluble in polar organic solvents. Conductivity studies showed an n-type semiconductor behavior (cr = 3 x 10 Scm at room temperature) that followed a one-term Arrhenius-type equation with increasing conductivity over the range 25-220 °G. 

The morphology (controlled, for example, by AFM) and the physical parameters (e.g. conductivity) depend largely upon the electrochemical polymerization conditions potentiostatic/potentiodynamic, solvent, conducting salt. Therefore the film properties such as conductivity and electrocatalysis must also be carefully optimized. 

Acids, bases, salts, and dissolved carbon dioxide may increase the conductivity of the solvent. The solvent conductivity can be increased remarkably by mixing chemically inert components. Substances, such as mineral salts, mineral acids, carboxylic acids, some complexes of acids with amines, stannous chloride, and some tetraalkylammonium salts, are added to the solvent to increase its conductivity. For organic acid solvents, small amount of water addition will significantly increase their conductivity due to ionization of the solvent molecules. This increase in the conductivity can help production of headless fibers just because stretching of the solution has increased, and to some degree a fiber diameter decrease can be observed. 

Dielectric constant A simple measure of solvent polarity (the electrostatic factor is a uoduct of dielectric constant and dipole moment). The electrical conductivity of solvent indicates if there is a need to earth (or ground) the equipment which handles solvent to prevent static spark ignition. Admixtures affect solvent conductivity. These are most important in electronics industry. 

Uyar T and Besenbacher F (2008) Electrospinning of uniform polystyrene fibers The effect of solvent conductivity, Polymer 49 5336-5343. 

Keywords mixed solvent conductance zeta potential surface charge adsorption surface sites... 

Bis(acetylacetonato)(oxo)vanadium (IV) has also been used instead of CuCI. When acetonitrile is used as solvent, conductivities around 10 Scm are obtained [37]. Those conductivity values increased by two orders of magnitude when pyridine was added to the solution. This suggests that pyridine coordinates with the copper ion, forming an active site. 

The measured electrolyte specific conductivity has a contribution due to the solvent conductivity. In the case of aqueous systems, the self-dissociation of water contributes in 0.055 j.S cm at 25 °C, but increases at higher temperatures and pressures due to the increase in K and the mobility of the and HO" ions. The ion product of water up to... 

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