Chlorides determination

Chlorides are usually measured by dissolving powder samples in acid. The samples are taken from drillings or from crushed cores. It is preferable to collect a series of drilHngs at different depths so that a chloride profile can be produced. If a single sample is taken it is recommended that it is taken at the reinforcement depth. 

Alternatively a core can be cut into slices and the slices crushed. Like the carbonation tests the chloride profile must be related to cover so that the extent to which rebars are exposed to high chlorides can be determined. 

Chloride profiles can also be used to determine the diffusion coefficient and thus predict the ongoing rate of ingress. However, to do this a minimum of four depth increments are required for sensible curve fitting. 

The corrosion thresholds were discussed in Section 3.2.3. It is important to recognize that these are approximate for the reasons discussed in Section 3.2.3. 

It is also important to realize that the chloride level at the rebar determines the present extent of corrosion, but the profile determines the future rate, as that is what drives more chlorides from the environment to the steel surface. 

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The structure of sodium chloride determined by the Braggs in 1913 was deeply disturbing to many chemists. In a letter to Nature in 1927, Lawrence Bragg made... 

Determination of soluble sodium chloride. By entering the graph in Figure 4-109 with the Ib/bbl of calcium chloride at the correct volume percent of water (by retort) line, the maximum amount of soluble sodium chloride can be found. If the sodium chloride content determined in Step 2 is greater than the maximum soluble sodium chloride determined from Figure 4-108, only the soluble portion should be used for calculating the total soluble salts. 

Reagent. Supporting electrolyte. Prepare a 0.5M potassium nitrate from the pure salt for chloride determinations the solution must be prepared with a mixture of equal volumes of distilled water and ethanol. 

Methyl chloride, determination by x-ray absorptiometry, 84 Mica, attenuation of x-rays by, 45 Microanalysis, use of x-rays in histo-chemical and eytochemical, 296-305... 

Impurities consist of unreacted material, including alkanes and internal or branched alkenes, and other material which can be detected in the neutral oil fraction of AOS. Examination of this fraction also indicates the amount of unhydrolyzed material (sulfonate esters and sultones) and byproducts (secondary alcohols, unsaturated and 2-chloro-y-sultones) in the sample. Salt calculations are made to determine inorganic sulfates and sodium chloride. Determinations for alkalinity, color, and water are required to meet product... 

A solution of sample in carbon tetrachloromethane is injected directly into the column and alkane- and monochloroalkanesulfonyl chloride determined as chloroalkane and dichloroalkane, respectively. 

The titrimetric determination of soil constituents is most commonly applied to a limited number of soil analyses, namely, organic carbon, nitrogen compounds, carbonates, and chlorides. Determination of acid content by titration is generally not done because the titration curves are not amenable to typical titration analysis. Because of the color of soil and the fact that it is a suspension when stirred, it is often necessary to remove the constituent of interest before titration. In other cases, it is possible to do a direct titration using an appropriate indicator. However, even in these cases, detection of the end point is difficult. 

How is the solubility product of silver chloride determined via a potentiometric titration ... 

Note. All of the RDX component and portions of the TNT and wax are added as Composition B. A separate calcium chloride determination need only be 9one if required in the contract or order (See 6.2). Percentage requirement of Calcium Chloride is 0.5% 0.1% Calcium Silicate shall be determined as specified in 4.4.1.2 when used in the formulation of HBX compounds. The Calcium Silicate content shall be a minimum of 1.25 weight percent of the TNT content of the mixture and shall only be used in the HBX compositions when specified by the procuring agency (See 6.2). Calcium Silicate is designated for use only in Army formulations of HBX type explosive compositions. The major portion of the wax and all of the Nitrocellulose and lecithin are added as Composition D-2 ... 

M phosphate buffer (pH 7.3) in 0.2 M sodium chloride determination of average molecular size of hyaluronic acid from synovial fluid 131... 

Under the influence of ultraviolet irradiation, chloride displaced the nitro group of 2-(5 -nitro-2 -furanyl)benzothiazole to give a chlorofuran exhibiting intense violet fluorescence. This allowed the reaction to be used as an analytical process for chloride determination (80CPB939). 

The detection and determination ot the perchlorates.—The perchlorates give no precipitates with silver nitrate or barium chloride soln. cone. soln. give a white crystalline precipitate with potassium chloride. Unlike all the other oxy-acids of chlorine, a soln. of indigo is not decolorized by perchloric acid, even after the addition of hydrochloric acid and they do not give the explosive chlorine dioxide when warmed with sulphuric acid unlike the chlorates, the perchlorates are not reduced by the copper-zinc couple, or sulphur dioxide. Perchloric acid can be titrated with —iV-alkali, using phenolphthalein as indicator. The perchlorates can be converted into chlorides by heat and the chlorides determined volumetrically or gravimetrically they can be reduced to chloride by titanous sulphate 28 and titration of the excess of titanous sulphate with standard permanganate they can be fused with zinc chloride and the amount of chlorine liberated can be measured in terms of the iodine set free from a soln. of potassium iodide and they can be... 

The use of different reducing agents allows us to produce particles of a prechosen size range. The speed of reduction of the gold chloride determines how many gold nuclei are formed. In a closed system, this will determine the... 

Malmstadt, H. V., and J. G. Winefordner Precision Null-Point Potentiometry. A Simple, Rapid and Accurate Method for Low Concentration Chloride Determination. Anal. Chim. Acta 20, 283 (1959). 

Methods 1 and 3 are EPA approved (Methods 325.3 and 325.1-2, respectively) for chloride determination in wastewater. For multiple ion determination, ion chromatography technique should be followed (see Section 1.8). 

The stated variability is certainly within acceptable limits, as are the recovery values reported. It would seem likely that there is room for this rapid, accurate automatic device for chloride determination in many laboratories. The cost of the silver wire reagent is low. There is some need for cleanliness and proper care of both the generator and indicator electrodes. 

One of the developments in electrometric titrations has produced at least one instrument for the determination of chloride which is simple, rapid, and accurate. For those institutions large enough to run many chloride determinations and with chloride allowed as an emergency test, the acquisition of such an instrument would be readily justified. Future development in electrometric methods might increase the importance of any of these instruments, particularly if it were adapted to more than one clinically important test. 

The following balanced chemical equation shows the reaction of aluminum with copper(II) chloride. If 0.25 g of aluminum reacts with 0.51 g of copper(II) chloride, determine the limiting reactant. 

Chloride Determine as directed in Sodium Chloride under Colors, Appendix IIIC. 

Chloride Determine as directed in the Chloride Limit Test under Chloride and Sulfate Limit Tests, Appendix IIIB, using the residue of the following Dissolve 500 mg of sample in 10 mL of hot water, add about 5 mg of sodium carbonate, and evaporate to dryness on a steam bath. Any turbidity produced does not exceed that shown in a control containing 15 (xg of chloride ion (Cl). 

Chloride Determine as directed in the Chloride Limit Test under Chloride and Sulfate Limit Tests, Appendix IIIB. Dissolve 1 g of sample in 100 mL of water. Any turbidity produced by a 10-mL portion of this solution does not exceed that shown in a control containing 70 p,g of chloride (Cl) ion. Ferric Iron Dissolve about 5 g of sample, accurately weighed, in a mixture of 100 mL of water and 10 mL of hydrochloric acid in a 250-mL glass-stoppered flask, add 3 g of potassium iodide, shake well, and allow to stand in the dark for 5 min. Titrate any liberated iodine with 0.1IV sodium thiosulfate, using starch TS as the indicator. Each milliliter of 0.1 N sodium thiosulfate is equivalent to 5.585 mg of ferric iron. 

Chloride Determine as directed in the Chloride Limit Test under Chloride and Sulfate Limit Tests, Appendix IIIA, using... 

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