Stability constant, chelating agents

The chelate HgY2 must be considerably more stable than MY( l 4)+ if necessary one can mask M"+ to a certain desirable extent by means of a selective com-plexing agent A, so that KM becomes an apparent stability constant,... 

Bioavailable trace elements in soil correlate with plant uptake and concentrations in plants. Extractants for bioavailable trace elements include chelating agents, diluted inorganic acid, neutral salt solutions, and water (Table 7.2). The most popular extractant for bioavailable trace elements in arid and semi-arid soils is DTPA-TEA (triethanolamine), which was developed by Lindsay and Norvell (1969, 1978) to extract available Cu, Zn, Fe and Mn from neutral and calcareous soils. Use of this chelating agent, DTPA, is based on the fact that it has the most favorable combination of stability constants for simultaneous complexation of Cu, Fe, Mn and Zn... 

A number of novel dioxo variants of the tetraazamacrocycles have been synthesized and stability constants were measured with Cu2+.114 A few of these were further evaluated as chelating agents with 64Cu.115 Structural differences included ring size (from 12 to 14) and placement of the oxo groups. Of the six variations synthesized, only one, l,4,8,ll-tetraazacyclotetradecane-3-9-dione(14N402-3,9), readily formed a complex (Figure 9). 

If one chooses a chelating agent with a relatively high stability constant, such as EDTA, one may find some ideal separation of nucleation and growth stages as a decisive prerequisite for monodispersed particles formation, since a drastic change of supersaturation can be expected in a system with metal ions around the stoichio-... 

From a spectrophotometric study of the equilibria between various chelating agents and [Cr2(02CMe)4] some stability constants of mononuclear Cr11 complexes have been determined... 

Stability constants for complexation of Hg2"1" by a variety of potentially octadentate N4S4 chelating agents have been determined the order of stability Hg > Zn > Cd was also noted.917 ... 

The separation of rare earths by anion exchange resins depends on somewhat different factors for a given chelating agent than to the cation exchange resins. For EDTA in an anion exchange process the order of elution is not the inverse order of the stability constants as in cation exchange process, rather [79] 4... 

For thermodynamic (stability constants) and kinetic data involving crown-type inclusion complexes see References r38 and r39 structural results in References r40-r42 (see also Chelating agents). 

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