ChemInform Abstract: Redox Potentials of Vanadium-Containing Couples. Part 1. An Electrolytic, Optical, Potentiometric Method for the Determination of the Formal Vanadium(V)/Vanadium(IV) Potential in Aqueous Sodium Chloride.

ChemInform ◽  
1989 ◽  
Vol 20 (24) ◽  
Author(s):  
S. ORECCHIO ◽  
V. ROMANO ◽  
R. ZINGALES
Keyword(s):  
Sodium Chloride ◽  
Potentiometric Method ◽  
Redox Potentials ◽  
Aqueous Sodium

DETERMINATION OF TRACE AMOUNTS OF SILVER IN GALENA ORES

1960 ◽  
Vol 38 (9) ◽  
pp. 1488-1494 ◽  
Author(s):  
E. J. Bounsall ◽  
W. A. E. McBryde
Keyword(s):  
Aqueous Solution ◽  
Nitric Acid ◽  
Sodium Chloride ◽  
Hydrochloric Acid ◽  
Chloride Solution ◽  
Sodium Chloride Solution ◽  
Silver Content ◽  
Aqueous Sodium Chloride Solution ◽  
Aqueous Sodium

An analytical method is described for the determination of microgram amounts of silver in galena ores, based on the "reversion" of silver dithizonate. Silver is separated from relatively large amounts of lead by extraction as dithizonate into chloroform from an aqueous 1:99 nitric acid solution. Separation from mercury, which is also extracted under these conditions and would, if present, interfere in the analysis, is achieved by reverting the dithizonate solution with a 5% aqueous sodium chloride solution which is also 0.015 molar in hydrochloric acid. Following dilution of this aqueous solution and adjustment of pH, silver is again extracted into chloroform as the dithizonate, and determined absorptiometrically. Analyses of a number of galena ore samples showed a precision of within 3% for a silver content ranging from 0.03 to 0.4%.Some other methods for isolating silver from these samples, which were tried but found unsatisfactory, are discussed.

Loss of Chloride in the Official Method for the Determination of Sodium Chloride in Cereal Foods

1976 ◽  
Vol 59 (6) ◽  
pp. 1396-1400 ◽  
Author(s):  
Wallace S Brammell
Keyword(s):  
Sodium Chloride ◽  
Sodium Carbonate ◽  
Potentiometric Method ◽  
Official Method ◽  
Cross Reference

Abstract The official final action method for sodium chloride in cereal foods, 14.129, was found to give erroneously low results because of loss of chloride during ashing. Comparison of the data with values obtained by the official first action potentiometric method, 32.A01–32.A06, which does not require ashing, showed that large and variable losses of chloride occurred. Official ashing methods for other foods specify addition of sodium carbonate to prevent conversion of chloride to volatile forms, but this was not specified in 14.129. In the present study it was found that sodium carbonate did not completely prevent loss of chloride. The official first action potentiometric method, 32.A01–32.A06, has been adopted as official first action for the determination of chloride in cereal foods to replace 14.129, which was repealed, official first action. A cross-reference to 32.A01–32.A06 has been added to 14.096.

scholarly journals Determination of the Molality Scale Dissociation Constants for Formic, Propionic and n-Butyric Acids in Aqueous Sodium Chloride Solutions at 298.15 K.

1996 ◽  
Vol 50 ◽  
pp. 492-498 ◽  
Author(s):  
Jaakko Ilmari Partanen ◽  
K.-M. Marstokk ◽  
Armin de Meijere ◽  
Harald Møllendal ◽  
Inge L. Møller ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Dissociation Constants ◽  
Chloride Solutions ◽  
Aqueous Sodium ◽  
Sodium Chloride Solutions

Comparison of the Volhard and Potentiometric Methods for the Determination of Chloride in Meat Products: Collaborative Study

1985 ◽  
Vol 68 (3) ◽  
pp. 480-484
Author(s):  
Paul R Beljaars ◽  
William Horwitz
Keyword(s):  
Sodium Chloride ◽  
Collaborative Study ◽  
Meat Products ◽  
Potentiometric Method ◽  
Collaborative Studies ◽  
Relative Standard ◽  
Luncheon Meat ◽  
Iso 5725 ◽  
Good Agreement

Abstract A collaborative study of the determination of chloride in meat products was conducted by the International Organization for Standardization (ISO) to compare the ISO 1841 method (Volhard titration) with the FAO/WHO Codex Alimentarius Committee method (potentiometric titration). Five canned luncheon meat products containing 0.25-2.0% sodium chloride at 4 different spiking levels were analyzed by 11 laboratories. The data were analyzed by ISO statistics (ISO 5725) and by AOAC statistics (Youden-Steiner), the major differences being in the rejection of outliers and in the statement of precision parameters. Good agreement was found between the mean chloride contents of the products as determined by both methods and with the added amounts, although statistically significantly higher sodium chloride recoveries were obtained with the potentiometric method. The within-laboratory variability (repeatability) is greater for the Volhard method, especially for chloride levels below 1.0%. Therefore it is proposed to set the lowest level of determination for the Volhard method at about 1.0% sodium chloride. The among-laboratories variability (reproducibility) of the potentiometric method was comparable with the results from the collaborative studies for chloride in cheese, giving acceptable values for relative standard deviations of 1.5-3.0% for meat products with 0.3-2.0% added sodium chloride. It is recommended that further work be conducted to reduce or eliminate the systematic error present with the potentiometric method as applied to meat and meat

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