Calibration of a glass electrode gave a reading of 139.3 mV with a 0.05 m potassium hydrogen phthalate buffer standard ( pH = 4.015), and a reading of -160.7 mV with a 0.01 m borax buffer standard (pH = 9.139), both measured at 30 °C. What is the observed slope (mV/pH unit) of the calibration curve? slope observed = What is the theoretical slope at 30 °C? slope theoretical What is the pH of an unknown that gives a reading of 42.5 mV with this electrode at 30 °C? pH = mV/pH mV/pH

Calibration of a glass electrode gave a reading of 139.3 mV with a 0.05 m potassium hydrogen phthalate buffer standard ( pH = 4.015), and a reading of -160.7 mV with a 0.01 m borax buffer standard (pH = 9.139), both measured at 30 °C. What is the observed slope (mV/pH unit) of the calibration curve? slope observed = What is the theoretical slope at 30 °C? slope theoretical What is the pH of an unknown that gives a reading of 42.5 mV with this electrode at 30 °C? pH = mV/pH mV/pH

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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