3. The lead in a swab sample, lead standards, together with a blank were made up in5.00 mL volumetric flasks using 0.2 % HNO3. 20 μL aliquots of these solutions wereinjected into the spectrophotometer and the absorbance measured at 217 nm. Thefollowing results were obtained.lead / ppbAbsorbance00.059110.000.085850.000.1926100.00.3260150.00.4594200.00.5929Swab sample0.3700(a) Determine the amount of lead in the swab sample in μg.

The amount of lead in the swab sample is approximately 9.44 µg.Explanation:

Answered: 3. The lead in a swab sample, lead…

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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The students conducted the assay for LDH activity using the two serum samples. Each cuvette (path length 1 cm) contained 3ml of a suitable assay buffer (including pyruvate as substrate). 20 microlitres of either serum was added to the cuvette and the absorbance values immediately recorded at the optimum wavelength for a period of 5 minutes (absorbance readings taken every 30 seconds). Protein concentration of serum sample (mg/ml) Change in absorbance at optimum wavelength per minute Control serum (C) 8 -0.04 Diseased serum (D) 7.8 -0.6 1c. Using the molar absorption coefficient of NADH as 6220 M-1 cm-1, and by application of the Beer-Lambert law, estimate the enzyme activity in the two samples (C and D). Express activity as moles per second. 1d. Estimate the specific activity of the two samples (moles per second per microgram).
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