The kinetics of crystallization of potassium bromide from aqueous solution

The kinetics of the reactions of iron(III) with 6-methyl-2,4-heptanedione and 3,5-heptanedione to form the corresponding monocomplexes have been studied spectrophotometrically in the range 5 °C to 16 °C at I 25 mol l-1 in aqueous solution. In the proposed mechanism for the two complexes, the enol form reacts with the metal ion by parallel acid-independent and inverse-acid paths. The kinetic constants for both pathways have been calculated at five temperatures. Activation parameters have also been calculated. The results are consistent with an associative activation for Fe(H2O)63+ and dissociative activation for Fe(H2O)5(OH)2+. The differences in the results for the complexes of heptanediones studied are interpreted in terms of steric factors.

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Temperature Effect on the Two-Dimensional Phase Transition Kinetics of Adenine Adsorbed at the Hg Electrode/Aqueous Solution Interface

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20031407 ◽

2003 ◽

Vol 68 (8) ◽

pp. 1407-1419 ◽

Cited By ~ 3

Author(s):

Claudio Fontanesi ◽

Roberto Andreoli ◽

Luca Benedetti ◽

Roberto Giovanardi ◽

Paolo Ferrarini

Keyword(s):

Phase Transition ◽

Aqueous Solution ◽

Phase Change ◽

Temperature Effect ◽

Transition Rate ◽

Effect Of Temperature ◽

Two Dimensional ◽

Solution Interface ◽

Phase Transition Kinetics ◽

Kinetics Of

The kinetics of the liquid-like → solid-like 2D phase transition of adenine adsorbed at the Hg/aqueous solution interface is studied. Attention is focused on the effect of temperature on the rate of phase change; an increase in temperature is found to cause a decrease of transition rate.

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Kinetics of the reactions of olefins with halogens in aqueous solution. Part II. Reactions of bromine with various olefins, and of hydrogen bromide with some epoxides

Journal of the Chemical Society B Physical Organic ◽

10.1039/j29660001119 ◽

1966 ◽

pp. 1119 ◽

Cited By ~ 5

Author(s):

R. P. Bell ◽

M. Pring

Keyword(s):

Aqueous Solution ◽

Hydrogen Bromide ◽

Kinetics Of

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Reordering and Crystallization of Silicon Carbide Amorphized by Neutron Irradiation

MRS Proceedings ◽

10.1557/proc-650-r5.1 ◽

2000 ◽

Vol 650 ◽

Author(s):

Lance L. Snead ◽

Martin Balden

Keyword(s):

Thin Film ◽

Silicon Carbide ◽

Crystallization Kinetics ◽

Neutron Irradiation ◽

Onset Temperature ◽

Kinetics Of Crystallization ◽

Crystallization Onset Temperature ◽

Crystallization Onset ◽

Kinetics Of

ABSTRACTDensification and crystallization kinetics of bulk SiC amorphized by neutron irradiation is studied. The temperature of crystallization onset of this highly pure, fully amorphous bulk SiC was found to be between 875-885°C and crystallization is nearly complete by 950°C. In-situ TEM imaging confirms the onset of crystallization, though thin-film effects apparently alter the kinetics of crystallization above this temperature. It requires >1125°C for complete crystallization of the TEM foil. Annealing at temperatures between the irradiation and crystallization onset temperature is seen to cause significant densification attributed to a relaxation, or reordering, of the as-amorphized structure.

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