Calibration of a glass electrode gave a reading of 129.7 mV with a saturated potassium hydrogen tartrate buffer standard ( pH = 3.557), and a reading of –98.7 mV with a 0.008695 m potassium dihydrogen phosphate, 0.0343 m disodium hydrogen phosphate buffer standard (pH = 7.400), both measured at 30 °C. What is the observed slope (mV/pH unit) of the calibration curve? slopeobserved mV/pH What is the theoretical slope at 30 °C? slope heoretical mV/pH What is the pH of an unknown that gives a reading of 18.5 mV with this electrode at 30 °C? pH = II

Calibration of a glass electrode gave a reading of 129.7 mV with a saturated potassium hydrogen tartrate buffer standard ( pH = 3.557), and a reading of –98.7 mV with a 0.008695 m potassium dihydrogen phosphate, 0.0343 m disodium hydrogen phosphate buffer standard (pH = 7.400), both measured at 30 °C. What is the observed slope (mV/pH unit) of the calibration curve? slopeobserved mV/pH What is the theoretical slope at 30 °C? slope heoretical mV/pH What is the pH of an unknown that gives a reading of 18.5 mV with this electrode at 30 °C? pH = II

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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