Effect of temperature on the association constants of some divalent metal ions with chloride in sea water-like solutions

<p>Association constants for the formation of lead (II) chloride complexes were studies in aqueous solutions also containing copper (II) and cadmium (II) ions.</p><p>The ionic strength was adjusted with sodium perchlorate to resemble that of sea water. The temperature was set at fixed values between 5° and 35° C to determine the effect on the equilibria in these systems. The total metal concentration was less than 10^-8 M.</p><p>Differential pulse anodic striping voltammetry was used with a conventional three electrode system and a thin-film working electrode of Pt/Hg. Complex formation was followed as a function of the ligand concentration by observing the shift in the stripping peak potential E_p.<p>The measured E^p and temperature data were used to obtain thermodynamic information on the formation of the complex ions. The activity coefficients were assumed constant at a given temperature.</p><p>The values for the base ten logarithm of the overall formation constants at 25.0° are 1.11, 1.48 and 1.83 for PbCl⁺, PbCl°_{2</p> and PbCl<sup>-}₃ complexes respectively. These results are in good agreement with literature values. The Δ H of formation values for those complexes in solution were found to be positive. Tentative results were obtained for copper (II) which was only weakly complexed with Cl<p>-</p> under the present conditions.</p>

Name thesis:degree_name

Master of Science (M.S.)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Graduate School

Year dc:date.available

1984

Author dc:creator

• Zamora, Jose Vinicio Macias

Contributors dc:contributor

• Patrick R. Jones

• Metals Effect of temperature on
• Chemical equilibrium
• Metal ions
• Heavy metals
• Lead
• Copper
• Cadmium
• Physical Sciences and Mathematics

Licence

• http://rightsstatements.org/vocab/NKC/1.0/

Repository record dc:identifier

https://scholarlycommons.pacific.edu/uop_etds/482

OAI identifier oai:identifier

oai:scholarlycommons.pacific.edu:uop_etds-1481