Equivalent conductance chloride

The specific heat of aqueous solutions of hydrogen chloride decreases with acid concentration (Fig. 4). The electrical conductivity of aqueous hydrogen chloride increases with temperature. Equivalent conductivity of these solutions ate summarized in Table 8. Other physicochemical data related to... 

Salts such as silver chloride or lead sulfate which are ordinarily called insoluble do have a definite value of solubility in water. This value can be determined from conductance measurements of their saturated solutions. Since a very small amount of solute is present it must be completely dissociated into ions even in a saturated solution so that the equivalent conductivity, KV, is equal to the equivalent conductivity at infinite dilution which according to Kohlrausch s law is the sum of ionic conductances or ionic mobilities (ionic conductances are often referred to as ionic mobilities on account of the dependence of ionic conductances on the velocities at which ions migrate under the influence of an applied emf) ... 

Equivalent Conductivities in rec. ohm cm of Chlorides at their Melting Points... 

In dilute solution the rare earth salts behave as 1 3 electrolytes and obey the Onsager equation in a modified form up to a concentration of 0.01 N. The behaviour of various rare earth salts, such as chlorides, bromides, nitrates and perchlorates has been examined [209—212]. The equivalent conductivity data for the rare earths is compiled in Table 11. Extensive ion-pair formation has been observed for rare earth sulphate solutions. 

The concentration dependencies of both the equivalent conductivity (A) and the chloride ion activity coefficient (fa) of the monomer DADMAC are not different... 

FIG. 1 Equivalent conductance (A) for sodium chloride (O), sodium acetate (O), and sodium propionate ( ) at 20°C against the square root of solute concentration (v/cb), as extracted from Fidaleo and Moresi (2005a,b, 2006). The continuous lines were calculated using Eq. 4 and the empirical parameters A0 and ft extracted from Fidaleo and Moresi (2005a,b, 2006). 

The value of A° of a given electrolyte can also be determined using equivalent conductances of other electrolytes with either identical cation or anion. So for instance the equivalent conductance of acetic acid can be determined if we add A° of hydrochloric acid and A0 of sodium acetate and substract A° of sodium chloride ... 

A 0.2 iV solution of sodium chloride was found to have a specific conductivity of 1.75 X 10 cm" at 18 °C the transport number of the cation in this solution is 0.385. Calculate the equivalent conductance of the sodium and chloride ions. (Constantinescu)... 

The self-diffusion coefficients of CF and Na" in molten sodium chloride are, respectively, 33 x 10 exp(-8500// 7) and 8x10 exp(-4000// 7) cm s". (a) Use the Nernst-Einstein equation to calculate the equivalent conductivity of the molten liquid at 935°C. (b) Compare the value obtained with the value actually measured, 40% less. Insofar as the two values are significantly different, explain this by some kind of structural hypothesis. 

The equivalent conductivities of some of the fused chlorides are given in Table 5.23, where the substances have been arranged according to the Periodic Table. The heavy line zigzagging across the table separates the ionic from the covalent chlorides. This structural difference is shown up sharply in the orders of magnitude of the equivalent conductivities. 

As a general rule increase of temperature increases the equivalent conductance both at infinite dilution and at a definite concentration the conductance ratio, however, usually decreases with increasing temperature, the effect being greater the higher the concentration. These conclusions are supported by the results for potassium chloride solutions in Table XI taken from the extensive measurements of Noyes and his... 

In order to determine the equivalent conductance of a sparingly soluble salt it is the practice to add the conductances of the constituent ions thus for silver chloride and barium sulfate the results are as follows ... 

From Kohlrausch s measurements on the conductance of saturated solutions of pure silver chloride the specific conductance at 25 may be estimated as 3.41 X lO" ohm cm. the specific conductance of the water used was 1.60 X 10 ohm cm. , and so that due to the salt may be obtained by subtraction as 1.81 X 10 ohm cm. This is the value of K to be employed in equation (26). From Table XIII the equivalent conductance of silver chloride at infinite dilution is 138.3 ohms cm.2 at 25 , and so if this is assumed to be the equivalent conductance in the saturated solution of the salt, it follows from equation (26) that... 

By means of this first approximation for the concentration of the saturated solution of silver chloride, it is poasible to make a more exact estimate of the actual equivalent conductance by means of the Onsager equation (p. 89) a more precise value of the solubility may then be determined. In the particular case of silver chloride, however, the difference is probably within the limits of the experimental error. 

Use the data in Tables X and XIII to estimate the equivalent conductance of 0.1 N sodium chloride, 0.01 N barium nitrate and 0.001 n magnesium sulfate at 25 . (Compare the results with the values in Table VUI.)... 

A 0.01 N solution of hydrochloric acid (A = 412.0) was placed in a cell having a constant of 10.35 cm." , and titrated with a more concentrated solution of sodium hydroxide. Assuming the equivalent conductance of each electrolyte to depend only on the total ionic concentration of the solution, plot the variation of the cell conductance resulting from the addition of 25, 50, 75, 100, 125 and 150 per cent of the amount of sodium hydroxide required for complete neutralization. The equivalent conductance of the sodium chloride may be taken as 118.5 ohms" cm. the change in volume of the solution during titration may be neglected. 

The following values were obtained by Shedlovsky [/. Am. Chem. equivalent conductance of potassium chloride at various concentrations at 25 ... 

Saxton and Waters [J. Am. Chem. Soc., 59, 1048 (1937)] gave the ensuing expressions for the equivalent conductances in water at 25 of hydrochloric acid, sodium chloride and sodium a-crotonate (Naa-C.) ... 

The second method of extrapolation is to obtain the values of X at various concentrations and to extrapolate the results to infinite dilution. The equivalent conductances of the chloride ion at several concentrations obtained from transference and conductance measurements, on the four chlorides to which the data in Table XXXI refer, are given in Table XXXII. These results can be plotted against the square-root of the... 

Since the ion conductance of the chloride ion is now known accurately, that of the hydrogen, lithium, sodium, potassium and other cations can be derived by subtraction from the equivalent conductances at infinite dilution of the corresponding chloride solutions from these results the values for other anions, and hence for further cations, can be obtained. The data recorded in Table XIII, page 56, were calculated in this manner. 

It is of interest to note from Table XXXII that the equivalent conductance of the chloride ion is almost the same in all four chloride solutions at equal concentrations, especially in the more dilute solutions. This fact supports the view expressed previously that Kohlrausch s law of the independent migration of ions is applicable to dilute solutions of strong electrolytes at equivalent concentrations, as well as at infinite dilution. 

Utilize the results to evaluate the equivalent conductance of the ammonium and chloride ions at infinite dilution by the method described on page 126. 

The theoretical basis of the use of a bridge containing a concentrated salt solution to eliminate liquid junction potentials is that the ions of this salt are present in large excess at the junction, and they consequently carry almost the whole of the current across the boundary. The conditions will be somewhat similar to those existing when the electrolyte is the same on both sides of the junction. When the two ions have approximately equal conductances, i.e., when their transference numbers are both about 0.5 in the given solution, the liquid junction potential will then be small [cf. equation (36a)]. The equivalent conductances at infinite dilution of the potassium and chloride ions are 73.5 and 76.3 ohins cm. at 25, and those of the ammonium and nitrate ions are 73.4 and 71.4 ohms cm. respectively the approximate equality of the values for the cation and anion in each case accounts for the efficacy of potassium chloride and of ammonium nitrate in reducing liquid junction potentials. 

Continued elution with Na+OH" causes the sample ions to leave the column and pass through a small detector cell. If a conductivity detector is used, the conductance of all of the anions, plus that of the cations (Na+ in this example) will contribute to the total conductance. If the total ionic concentration remains constant, how can a signal be obtained when a sample anion zone passes through the detector The answer is that the equivalent conductance of chloride (76 ohm cm equiv" ) and bromide (78) is much lower than that of OH" (198). The net result is a decrease in the conductance measured when the chloride and bromide zones pass through the detector. 

A more typical ion to detect might be chloride. The equivalent conductance is higher so a higher signal would result from this ion, assuming the same peak width and the same sodium counterion. If hydronium ion rather than sodium is the counterion to chloride, then the signal will be multiplied by another factor of 3.4. 

This ratio is given in the final column of the following table The x, Aj, and yi refer throughout to KCl, which is taken as a standard of comparison A0 lt Ao 01, and AM denote the equivalent conductivities of the various chloride solutions at o xN, o 01N, and at infinite dilution The product A x C1 may be conveniently termed the equivalent conductivity of the chloride ion constituent of the salt in question, bemg equal to FyV The constancy of this quantity (cf fifth col of the following table) as well as the constancy of the values in the last column is evident... 

This constancy of the equivalent conductivity of the chloride ion constituent at any given concentration does not, however, show whether... 

Fig. 5, in which the equivalent conductance, A, of aqueous solutions of potassium chloride at 25° is plotted as ordinates against the logarithms of the dilution, V, represents, in general trend at least, the variation of the equivalent conductance with dilution of aqueous solutions of all salts, and of strong acids and bases. These equivalent con-... 

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