Calibration of a glass electrode gave a reading of 139.1 mV with a 0.05 m potassium dihydrogen citrate buffer standard ( pH = 3.766), and a reading of -75.5 mV with a 0.08 m HEPES, 0.08 m NaHEPES, 0.08 m NaCl buffer standard (pH = 7.454). both measured at 30 °C. What is the observed slope (mV/pH unit) of the calibration curve?

Calibration of a glass electrode gave a reading of 139.1 mV with a 0.05 m potassium dihydrogen citrate buffer standard ( pH = 3.766), and a reading of -75.5 mV with a 0.08 m HEPES, 0.08 m NaHEPES, 0.08 m NaCl buffer standard (pH = 7.454). both measured at 30 °C. What is the observed slope (mV/pH unit) of the calibration curve?

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

ChapterA1: Evaluation Of Analytical Data

Section: Chapter Questions

Problem A1.23QAP

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