The program VLpH is designed for use in the calibration of a glass electrode in terms of hydrogen ion concentration at very low pH, where deviations from the Nernst law are observed. The electrode response is assumed to follow a modified Nernst law, eq. (1), in which E is a measured electrode potential, E0 is the "standard" electrode potential, s is a slope factor and jp is a "junction potential" correction factor.
E = E0 + s log10[H+] + jp [H+] (1)
The calibration process is accomplished in two stages.
Eadj= E - jp [H+] = E0 + s log10[H+] (2)
The program VLpH is available for download, free of charge. Simply click on the link below. The installation pack includes a help file (including details of experimental procedures) and examples of calibration data and data for adjustment. Comments and queries to: email@example.com
Download VLpH installer (self-extracting installation file)
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