Ethylenediaminetetraacetic acid titrations

Water hardness is the total calcium and magnesium ion concentration in a water sample and is expressed as the concentration of calcium carbonate. Temporary hardness is that part of the total hardness that disappears on boiling. Whilst not being accepted as a standard method, the use of ion-selective electrodes allows a rapid measurement of water hardness and can be used to determine changes in hardness. The direct potentiometric method is not recommended for the ion-selective electrode but an indirect potentiometric method involving ethylenediaminetetraacetic acid titration is recommended. The ion-selective electrode that is used is a liquid ion-exchange electrode that responds to the divalent ions magnesium and calcium. 

The utility of complexation titrations improved following the introduction by Schwarzenbach, in 1945, of aminocarboxylic acids as multidentate ligands capable of forming stable 1 1 complexes with metal ions. The most widely used of these new ligands was ethylenediaminetetraacetic acid, EDTA, which forms strong 1 1 complexes with many metal ions. The first use of EDTA as a titrant occurred in... 

Metal Content. Two common analytical methods for determining metal content are by titration and by atomic absorption spectrophotometry (aas). The titration method is a complexiometric procedure utilizing the disodium salts of ethylenediaminetetraacetic acid (EDTA). The solvent, indicator. 

Such reactions are not available for Bi but this can readily be determined by complexometric titration using ethylenediaminetetraacetic acid or similar complexones ... 

Definitions. Titrimetric Reactions. Acid-base Titrations. Applications of Acid-base Titrations. Redox Titrations. Applications of Redox Titrations. Complexometric Titrations. Ethylenediaminetetraacetic Acid (EDTA). Applications of EDTA Titrations. Titrations with Complexing Agents Other Than EDTA. Precipitation Titrations. ... 

A common reagent used in complexometric titrations is ethylenediaminetetraacetic acid (EDTA). It is often used to determine the concentration of metal ions present in a solution. 

Although the most sensitive line for cadmium in the arc or spark spectmm is at 228.8 nm, the line at 326.1 nm is more convenient to use for spectroscopic detection. The limit of detection at this wavelength amounts to 0.001% cadmium with ordinary techniques and 0.00001% using specialized methods. Determination in concentrations up to 10% is accomplished by solubilization of the sample followed by atomic absorption measurement. The range can be extended to still higher cadmium levels provided that a relative error of 0.5% is acceptable. Another quantitative analysis method is by titration at pH 10 with a standard solution of ethylenediaminetetraacetic acid (EDTA) and Eriochrome Black T indicator. Zinc interferes and therefore must first be removed. 

The excess Ni2+ was then titrated with 10.15 mL of 0.013 07 M ethylenediaminetetraacetic acid (EDTA) ... 

EDTA (ethylenediaminetetraacetic acid) (H02CCH2)2NCH2CH2N-(CH2C02H)2, the most widely used reagent for complexometric titrations. It forms 1 1 complexes with virtually all cations with a charge of 2 or more, effective formation constant Equilibrium constant for formation of a complex under a particular stated set of conditions, such as pH, ionic strength, and concentration of auxiliary complexing species. Also called conditional formation constant. 

The ester function was determined by alkaline hydrolysis followed by precipitating the liberated acids as calcium salts. In the present work, samples of 1-1.5 grams were added to 50 ml. of 0.2N aqueous sodium hydroxide and refluxed with continuous stirring under nitrogen for 18-24 hours. After hydrolysis the samples were titrated to a pH of 9 with hydrochloric acid. Then 15 ml. of IN calcium acetate was added, and the sample was stirred rapidly under a stream of nitrogen for 1 hour. The suspension of calcium salt was filtered, washed with dilute base until free of excess calcium acetate as determined by titration with ethylenediaminetetraacetic acid (EDTA), and dried under a stream of nitrogen. Calcium was determined on the dried product. 

Although mercury seldom is used as an indicator electrode in redox titrations (because it is so readily oxidized), it is used extensively for potentiometric titrations with complexing agents such as ethylenediaminetetraacetic acid... 

Foreman, J. K., and Smith, T. D. The nature and stability of the complex ions formed by ter-, quadri-. and sexa-valent plutonium ions with ethylenediaminetetraacetic acid. Part I. pH titrations and ion exchange studies, J. Chem. Soc.,... 

EDTA An abbreviation of ethylenediaminetetraacetic acid, a chelating agent widely used for complex formation titrations. Its formula is (HOOCCH2)2NCH2CH2N(CH2COOH)2. 

Essential water Water in a solid that exists in a fixed amount, either within the molecular structure (water of constitution) or within the crystalline structure (water of crystalli-atioii). Ethylenediaminetetraacetic acid Probably the most versatile reagent for complex formation titrations forms chelates with most cations. See EDTA. 

Years ago, the indicator used for the titration of calcium and magnesium was a soap solution. As long as calcium and magnesium were present, no soap suds would form. The solution was shaken continuously as the titrant was added, and the first appearance of soap suds was the endpoint. This was a difficult endpoint to reproduce. The discovery by Swartzenback that ethylenediaminetetraacetic acid (EOTA) would chelate with calcium and magnesium ended the soap... 

The solubility of the complex anion Ag(CN)2 in contrast to the high insolubility of neutral silver cyanide (AgCN) was exploited for the determination of silver (and/or cyanide) by Justus von Liebig as long ago as 1851 this procedure may well be cited as the best established complexometric titration preceding the great developments brought about by G. Schwarzenbach in 1940 when he pioneered the use of ethylenediaminetetraacetic acid, EDTA, and other aminopolycarboxylic acids as titrants" and opened up new vistas in titrimetry (see Section 10.6). 

Ethylenediaminetetraacetic acid can be used as a reagent for the titration of Ti(lV). However, the reaction proceeds slowly, and the Ti(IV) species tend to hydrolyze during the titration, so that a back-titration method is necessary to make the complexometric method work properly [26]. 

The copper content of the complex will be determined by a disodium ethylenediaminetetraacetic acid (EDTA) titration. Disodium EDTA or "EDTA," in short, is a hexadentate chelating ligand, a ligand which can potentially bond one copper ion at a maximum of six coordination sites. 

Ethylenediaminetetraacetic acid (EDTA) com-plexometric titrations are based on the fact that many metallic ions form stable complexes with this tetradentate ligand, EDTA. The endpoints are detected using complexing agents capable of forming complexes with the metallic species to be determined and having lower coordination constants than those of the complexes that are formed with EDTA and that also have different colors in their free and com-plexed states. 

The determination of calcium in meat products, especially in mechanically recovered (or separated) meat (MRM/MSM), is an important estimation of the amount of bone material included in the meat. The AOAC method describes an acid digestion of the sample and reaction of an aliquot of the filtered digest with excess ethylenediaminetetraacetic acid (EDTA) under alkaline conditions to form a chelated complex with calcium ion. The excess EDTA is then titrated with calcium carbonate using hydroxynaph-thol blue as indicator. 

Titrimetric determination The mannitol or glycerol acid-base titration procedure is applied to the dissolved sodium carbonate melt for the determination of milligram amounts of B2O3. A blank prepared from a glass that does not contain boric oxide should be subjected to the same procedure. There are certain interferences the effect of fluoride is eliminated by adding calcium carbonate to the fusion mixture lead and zinc can be filtered off after dissolution of the melt phosphate is precipitated by addition of iron(ni) chloride. The influence of some interference from such elements as aluminum or titanium can be eliminated by adding ethylenediaminetetraacetic acid (EDTA). 

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