Studies on nucleation from solution of some analytically important metal chelates-II Nickel dimethylglyoximate.

A new direct-mixing and rapid particle-counting system useful for studies on crystal nucleation solution is described. The methods used to calibrate and evaluate the system are reported together with the results obtained during studies on nucleation from solution of nickel dimethylglyoximate. The Volmer-Weber, Becker-Döring model of the nucleation process is used to correlate the results.

Studies on nucleation from solution of some analytically important metal chelates.

The combination of precipitation from homogeneous solution and Vonnegut's droplet technique is employed in the study of nucleation from solution of bis(1,2-cyclohexanedionedioxunato)Ni(II), bis(1,2-cycloheptanedionedioximato)Ni(II), bis(1,2-cyclohexanedionedioximato)Pd(II) and bis(1,2-cycloheptanedionedioximato)-Pd(II). Values of the kinetic constant, surface energy, critical radius and the number of molecules per critical nucleus are calculated and discussed in terms of the limitations of the classical theory of nucleation when applied to crystal nucleation from aqueous solutions of electrolytes.

Homogeneous nucleation of bis(1,2-cyclohexanedionedioximato)palladium(II).

Precipitation from homogeneous solution has been applied to the drop technique for the study of the homogeneous nucleation of bis(1,2-cyclohexanedionedioximato)palladium(II). It was found that under the experimental conditions employed the interfacial energy of the chelate was 47 ergs.cm(-2) and the critical radius size 11 A.

Precipitation of bis(1,2-cyclohexanedionedioximato)palladium(II) from homogeneous solution.

The reaction between hydroxylamine and cyclohexanedione in the presence of palladium ions has been made the basis of the precipitation of bis(1,2-cyclohexanedionedioximato)palladium(II) from homogeneous solution. The procedure provides a means of separating palladium from Cu(II), Co(II), Ni(II) and Pt(IV), and is a simple, rapid and accurate method for determining palladium.

Precipitation of nickel salicylaldoximate from homogeneous solution.

The reaction between hydroxylamine and salicylaldehyde in the presence of nickel ions has been made the basis of the precipitation of nickel salicylaldoximate from homogeneous solution. Conditions for quantitative precipitation of nickel when present alone or with such metal ions as Fe(2+), Cr(3+), Al(3+), Zn(2+), Mn(2+) and Cd(2+) are described. The recommended procedure is shown to be useful in the analysis of a steel sample.

Precipitation from homogeneous solution applied to the drop technique for the study of nucleation.

The technique of precipitation from homogeneous solution has been successfully coupled with the drop technique for study of the nucleation process.

Precipitation of nickel and palladium dimethylglyoximates from homogeneous solution.

A comparison of the reaction mechanisms by which nickel or palladium dimethylglyoximate is precipitated from homogeneous solution by the reactions of biacetyl and hydroxylamine discloses many differences. Knowledge of the kinetics and mechanism of the reactions can be used to avoid formation of excess dimethylglyoxime, a limitation of the conventional methods of precipitation.