Ethylenediaminetetracetate

In a complexation reaction, the reaction unit is an electron pair. For the metal, the number of reaction units is the number of coordination sites available for binding ligands. For the ligand, the number of reaction units is equivalent to the number of electron pairs that can be donated to the metal. One of the most important analytical complexation reactions is that between the ligand ethylenediaminetetracetic acid (EDTA), which can donate 6 electron pairs and 6 coordinate metal ions, such as Cu thus... 

Uses, cx-Aminonitriles may be hydrolyzed to aminoacids, such as is done in producing ethylenediaminetetracetate (EDTA) or nittilotriacetate (NTA). In these cases, formaldehyde is utilized in place of a ketone in the synthesis. The principal use of the ketone-based aminonitriles described above is in the production of azobisnittile radical initiators (see below). AN-64 is also used as an intermediate in the synthesis of the herbicide Bladex. Aminonitriles are also excellent intermediates for the synthesis of substituted hydantoins by reaction with carbon dioxide however, this is not currently commercially practiced. 

Ligno sulfonate—metal complexes are weaker complexes than those formed from amine-based complexing agents such as ethylenediaminetetracetic acid (EDTA). They are compatible with most pesticides /herbicides, but thek use in phosphate fertilisers is not recommended. 

Some strains of P. aeruginosa are resistant to benzalkonium chloride and, in fact, can be grown in solutions concentrated in this agent. This has caused great concern because of the virulent nature of this organism in ocular infections, as discussed previously. Thus, it was an important finding in 1958 that the acquired resistance could be eliminated by the presence of ethylenediaminetetracetic acid (sodium edetate) in the formulation. This action of EDTA has been correlated with its ability to chelate divalent cations, and it is commonly used as a preservative aid [125]. The use of disodium EDTA, where compatible, is recommended in concentrations up to 0.1%. 

Sodium ethylenediaminetetracetate, Sodium hydroxide Schierwater, F.-W., Sichere Chemiearb., 1987, 39, 35... 

Sun, Y., L.J. Kirschenbaum, and I. Kouadio. 1991. Kinetics and mechanism of the multi-step oxidation of ethylenediaminetetracetate by Ag(OI I)4 in alkaline media. Jour. Chem. Soc., Dalton Trans. 1991 2311-2315. 

Aggett, J. and L.S. Roberts. 1986. Insight into the mechanism of accumulation of arsenate and phosphate in hydro lake sediments by measuring the rate of dissolution with ethylenediaminetetracetic acid. Environ. Sci. Technol. 20 183-186. 

Ethylenediaminetetracetic acid disodium salt TRIS Tris(hydroxy)aminomethane HMTA Hexamethylenetetramine... 

Procedure Weigh accurately about 0.8 g of granulated zinc, dissolve by gentle warming in 12 ml of dilute hydrochloric acid and 5 drops of bromine water. Boil to remove excess bromine, cool and add sufficient DW to produce 200 ml in a volumetric flask. Pipette 20 ml of the resulting solution into a flask and neutralize carefully with 2 N sodium hydroxide. Dilute to about 150 ml with DW, add to it sufficient ammonia buffer (pH 10.0) to dissolve the precipitate and add a further 5 ml quantity in excess. Finally add 50 mg of Mordant Black II mixture and titrate with the disodium edetate solution until the solution turns green. Each 0.003269 g of granulated zinc is equivalent to 1 ml of 0.05 M disodium ethylenediaminetetracetate. 

Procedure Weigh accurately about 0.3 g of magnesium sulphate heptahydrate and dissolve in 50 ml of DW. Add to it 10 ml of strong ammonia-ammonium chloride solution, and titrate with 0.05 M disodium ethylenediaminetetracetate employing 0.1 g of mordant black II mixture as indicator, until the pink colour is discharged from the blue. Each ml of 0.05 M disodium ethylenediaminetetracetate is equivalent to 0.00602 g of MgS04. 

A number of pharmaceutical inorganic substances may be assayed by the direct titration method using disodium ethylenediaminetetracetate. A few typical examples are cited in the following Table 9.2. 

Alternative strategies have also been proposed, in which the metal components are removed from the wood prior to incineration. These include extraction using phosphoric acid (Kazi and Cooper, 2002), ethylenediaminetetracetic acid (Nami Kartal, 2003) or oxalic acid combined with bacterial culture (Clausen, 2004a,b), and electrodialysis (Mateus etal., 2002). 

In these equations, edta = ethylenediaminetetracetate, dipy = dipyridyl, and en = ethylenediamine. Co(II) complexes are of two types those with a coordination number of 4 and those with 6. The former tend to be blue, while the latter are often pink to violet. Co(II) complexes are usually unstable, since they tend to be oxidized by air to Co(III) complexes. 

In the first step, a substrate coordinates to a metal catalyst and forms an intermediate mixed complex (LMS in Scheme 13). The substrate is then activated by metal ions and dissociates from the catalyst. The complex catalyst, having accomplished its purpose, is regenerated to the original complex. The catalytic action of a metal ion depends substantially on the nature of the ligands in the intermediate mixed complex. Certain ligands induce an increase in catalytic activity, while others, e.g. multidentate ligands such as ethylenediaminetetracetic acid, inhibit the catalytic action of a metal ion. Therefore, if a polymer ligand is used as one component of a metal-complex catalyst, its properties may affect the catalytic action of the metal ion. 

Why is it advisable to add ethylenediaminetetracetic acid (EDTA) to measure calcium when it is in the form of a phosphate ... 

Among the numerous commercial derivatives of ethylenediaminetetracetic acid (EDTA), a mixed salt of Zn, Na containing one atom of zinc and two atoms of sodium per molecule of EDTA is found. This mixed salt presents itself in the form of a crystallised hydrate. An attempt is described to deduce the number of water molecules of this hydrate by measuring the presence of zinc by atomic absorption. The experimental approach was as follows ... 

Such as Rhodapex CO-433 (Rhone-Poulenc) Tetrasodiurn ethylenediaminetetracetate (39%)... 

MEDTA. Dissolve 7.4 g ethylenediaminetetracetic acid (disodium salt) in 100 mL distilled water Raise the pH to 8 0, and autoclave. 

Sodium hypochlorite, Sodium ethylenediaminetetracetate, Sodium hydroxide, 4031... 

Ethylenediaminetetracetic acid, C10H16N2O8 (Sigma-Aldrich Corp.)... 

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