The drug Librium gives a polagraphic wave with E1/2 = -0.265 V (vs SCE) in 0.05 M H;SO4. A 50.0 mL sample containing Librium gave a wave height of 0.37 µA. When 2.00 mL of 3.00 mM Librium in 0.05 M H2SO4 was added to the sample, the wave height increased to 0.80 µA. Find the molarity of Librium in the unknown. Hydrogen peroxide in dilute concentrations can be analyzed by differential pulse polarography. Calibration led to the following relationship la = (7.002 x 107 nA )7[H,02] – 1.500 nA M. Find the hydrogen peroxide concentration in ppb for an unknown that gave a peak current of 300.0 nA.

The drug Librium gives a polagraphic wave with E1/2 = -0.265 V (vs SCE) in 0.05 M H;SO4. A 50.0 mL sample containing Librium gave a wave height of 0.37 µA. When 2.00 mL of 3.00 mM Librium in 0.05 M H2SO4 was added to the sample, the wave height increased to 0.80 µA. Find the molarity of Librium in the unknown. Hydrogen peroxide in dilute concentrations can be analyzed by differential pulse polarography. Calibration led to the following relationship la = (7.002 x 107 nA )7[H,02] – 1.500 nA M. Find the hydrogen peroxide concentration in ppb for an unknown that gave a peak current of 300.0 nA.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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Concept explainers

Spectroanalytical Methods

Spectroanalytical methods measure the wavelength and intensity of radiations that are either emitted or absorbed by a molecular or atomic species. These methods are useful for evaluating the electronic or atomic arrangement of the molecules of a given analyte.

Question

The drug Librium gives a polagraphic wave with E1/2 = -0.265 V (vs SCE) in 0.05
M H;SO4. A 50.0 mL sample containing Librium gave a wave height of 0.37 µA.
When 2.00 mL of 3.00 mM Librium in 0.05 M H2SO4 was added to the sample, the
wave height increased to 0.80 µA. Find the molarity of Librium in the unknown.
Hydrogen peroxide in dilute concentrations can be analyzed by differential pulse
polarography. Calibration led to the following relationship
la = (7.002 x 107
nA
)7[H,02] – 1.500 nA
M.
Find the hydrogen peroxide concentration in ppb for an unknown that gave a peak
current of 300.0 nA.

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