Masters Theses

Abstract

"Water adsorption isotherms on gold films were measured with a quartz crystal microbalance. Two gold films were studied: a "dirty" gold film contaminated by approximately one monolayer of carbon, and a "clean" gold film prepared by evaporating gold from a heated tungsten wire under high vacuum.

Water was found to chemisorb on both films according to a Freundlich type adsorption isotherm. Isosteric heats of adsorption were computed from the isotherm data. On the "clean" gold surface the isosteric heat showed a logarithmic decrease with increasing water coverage. The highest measured value for the heat of adsorption was 35 kcal mole-1 at a coverage of 0.6 x 1014 molecules cm-2. Above one monolayer coverage the heat of adsorption reached a constant value of 13 kcal mole-1.

In the range of coverages investigated on the "dirty" gold film the heat of adsorption decreased with increasing H2O coverage but did not show a logarithmic behavior. The maximum value measured was 19 kcal mole-1.

The experimental differential molar entropy of adsorption on "clean" gold was compared with theoretical entropies. It was found to be composed mainly of translational entropy. This and the decrease of the isosteric heat of adsorption with increasing water coverage favor a mobile water layer"--Abstract, page i.

Advisor(s)

Levenson, L. L., 1928-1998

Committee Member(s)

James, William Joseph
Venable, Raymond L., 1935-2008

Department(s)

Chemistry

Degree Name

M.S. in Chemistry

Publisher

University of Missouri--Rolla

Publication Date

1973

Pagination

vi, 45 pages

Note about bibliography

Includes bibliographical references (pages 39-40).

Rights

© 1973 Jean-Marc Louis Deschanel, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Subject Headings

Water -- Purification -- AdsorptionGold filmsHeat of adsorption

Thesis Number

T 2922

Print OCLC #

6020243

Electronic OCLC #

911633427

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