Computer Constructed Conductance Curves Frequently in analytical and physical chemistry courses electrolyte conductance is a topic of discussion. Although a number of computer programs have been developed for calculating electrolyte limiting equivalent conductances, association and dissociation constants, and electrolyte "sizes" in solution, no reported computer programs contain subroutines for plotting sets of A versus C'" data. Therefore, since the shape of such equivalent conductance plots qualitatively reveals the extent of association of an electrolyte, a program' written in extended Fortran IV for a Xerox Sigma Six computer system was developed for the construction of A-C'lz plots. The input t o the program consists of: title, dimensions of the plot, total number of plots, number of data points per plot, x-y limits and step size of the axes, number of digits to be printed on the r-y axes, cell constant, resistance of the electrolyte solutions and the solvent, and solution concentrations. Instead .,: uf considering the solution concentrations as original input data, the program, which computes A and C1t2, could be modified to calculate the concentrations. This modification would depend on the method of solution preparation. In addition to the plots, the output from the program consists of listings of C, R, C 1 / ' , and A. The figure, which represents the conduc7 tance behavior of several recently studied colloidal electrolytes in 2-methoxyethanal~illustrates a typical computer plot of A-C1"data. 1
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National Science Foundation Undergraduate ReI I search Participant, Summer 1974. (CONCENT4RTION PR Hooe Colleee Mellon Faeultv Develooment Grant Computer constructed conductance curves. (*I Octylamine hydrochloride: recipient, Summer 1975; to whom correspondence ( X ) dodecylamine hydrochloride: (0)trioctylamine hydrochloride. and computer program requests should be addressed. L
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H o w College Holland, Michigan 49423
234 / Journal of Chemical Education
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Demetra V. Collia3 Barbara J. Barke+
