1. at what wavelength was Pb determined?2. What is the slope of the calibration curve?3. What is the y-intercept of the calibration curve?4. The researcher determined the Pb content of water sample from a river suspected to be contaminated with Pb from a nearby factory by complexing with cyanidine and the absorbance measured was 0.405. What is the lead content of the water sample? Cyanidin is found in intensely colored flowers. A researcher complexed the flower extract to Lead (Pb)and formed a deep purple color. Cyanidin is an eco-friendly ligand that can be used in UV-Vis analysis.Instead of using toxic and expensive reagents, this was employed by the researcher. PbCl2 (278.1g/mol) of a mass 0.090 g was used in the experiment. It was dissolved in 100.0 mL of distilled, de-ionized water to prepare the stock solution. The X max was determined as follows:A (Wavelength, nm)400420440460480500520540A (Absorbance)0.080.100.200.250.300.400.500.60A (Wavelength, nm)560580600620640660680700A (Absorbance)0.500.400.300.250.200.100.050.03The researcher made a standard calibration curve by diluting the 10.00 mL, 20.00mL, 30.00mL, 40.00mL, and 50.00 mL solutions from the stock. Water was filled up to the 100-mL mark of the volumetricflasks. The absorbance of the solutions were then obtained, and the data are shown below.Concentration (ppm)90.00Absorbance0.01180.00.20270.00.30360.00.43450.00.55

1. at what wavelength was Pb determined? 2. What is the slope of the calibration curve? 3. What is the y-intercept of the calibration curve? 4. The researcher determined the Pb content of water sample from a river suspected to be contaminated with Pb from a nearby factory by complexing with cyanidine and the absorbance measured was 0.405. What is the lead content of the water sample

1. at what wavelength was Pb determined? 2. What is the slope of the calibration curve? 3. What is the y-intercept of the calibration curve? 4. The researcher determined the Pb content of water sample from a river suspected to be contaminated with Pb from a nearby factory by complexing with cyanidine and the absorbance measured was 0.405. What is the lead content of the water sample

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter6: Types Of Chemical Reactions And Solution Stoichiometry

Section: Chapter Questions

Problem 142IP: Tris(pentatluorophenyl)borane, commonly known by its aeronym BARF, is frequently used to initiate...

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