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...

See similar textbooks

Similar questions

A student weighed out 0.150 g of protein powder and dissolved it in 100 mL of water (Solution 1). The student then diluted this solution by transferring 1 mL into a 25 mL flask and diluting with water (Solution 2). Finally, 1 mL of that solution was transferred to a test tube and combined with 4 mL Bradford reagent. The absorbance of the solution in the test tube was 0.187. Assuming that the best fit linear line of the standard curve was y = 0.04144 x + 0.01521 (μ g mL), calculate the percent protein by mass in the original protein powder.
A 2.42 x 10-5 M sample of compound X in a solvent has an absorbance of 0.313 at 528 nm in a 1.000 cm cuvel alone has an absorbance of 0.058. What is the molar absorptivity of compound X? 5 € = M-¹.cm=¹ A different sample of compound X in the same solvent has an absorbance of 0.485 at 528 nm when measured with the same cuvette. What is the concentration of this second sample? [X] = mol X L
An unknown sample of Mn2+ gave an absorbance of 0.392 in an atomic absorption analysis. Then 2.00 mL of solution containing 100.0 ppm of Mn2+ (=μg/mL) was mixed with 90.0 mL of unknown, and the mixture was diluted to 100.0 mL in a volumetric flask. The absorbance of the new solution was 0.600. The blank reading for this experiment is 0.010. Denoting the initial, unknown concentration as [Mn2+]i, write an expression for the final concentration, [Mn2+]f, after dilution. Units of the concentration are ppm. In a similar manner, write the final concentration of added standard Mn2+, designated as [S]f. Find [Mn2+]i in the unknown.
Mass spectral measurements were made on 10 replicate low concentration Pb-EDTA samples: 152.7, 114.6, 128.1, 143.1, 112.1, 181.5, 133.1, 137.7, 127.1, and 144.7 counts. Ten measurements of a blank had a mean measurement of 27.7 counts. A sample containing 2.00 µM Pb-EDTA gave a measurement of 1601 counts. Estimate the signal and concentration detection limits for Pb-EDTA. signal detection limit: counts concentration detection limit: µM
The data in the table are used to create a calibration curve for the determination of RNA from its absorbance at 260 nm. Use a spreadsheet and the least-squares method to determine the slope and y-intercept of the best straight line fit to the calibration curve. Do not subtract the blank reading when creating the calibration curve. m = b = RNA (µg) 0.00 10.67 21.34 32.01 42.68 mass= Absorbance at 260 nm 0.224 0.512 0.769 1.145 1.465 Using the slope and intercept of the calibration curve, determine the quantity of RNA in a sample that gives an absorbance of 0.636. µg µg
A compound with a molecular weight of 229.61 g/mol was dissolved in 50.0 mL of water. 1.00 mL of this solution was placed in a 10.0 mL flask and diluted to the mark. The absorbance of this diluted solution at 510 nm was 0.472 in a 1.000 cm cuvet. The molar absorptivity of the compound, at 510 nm, is 6,310 M-1 cm-1. Calculate the concentration of the compound in the initial 50.0 mL solution. A. 1.50 x 10-5 M B. 7.48 x 10-5 M C. 7.48 x 10-4 M D. 7.48 x 10-6 M
The data in the table are used to create a calibration curve for the determination of RNA from its absorbance at 260 nm. Use a spreadsheet and the least-squares method to determine the slope and y-intercept of the best straight line fit to the calibration curve. Do not subtract the blank reading when creating the calibration curve. m= RNA (µg) 0.00 10.29 20.58 30.87 41.16 mass= Absorbance at 260 nm 0.227 0.452 0.786 1.078 1.296 Hg-1 Using the slope and intercept of the calibration curve, determine the quantity of RNA in a sample that gives an absorbance of 0.523. µg
A student weighed out 0.150 g of protein powder and dissolved it in 100 mL of water (Solution 1). The student then diluted this solution by transferring 1 mL into a 25 mL flask and diluting with water (Solution 2). Finally, 1 mL of that solution was transferred to a test tube and combined with 4 mL Bradford reagent. The absorbance of the solution in the test tube was 0.11. Assuming that the best fit linear line of the standard curve was y = 0.04144 x + 0.01521 (μ g mL), calculate the percent protein by mass in the original protein powder.
A solution of a dye was analyzed by spectrophotometry, and the following calibration data were collected using a 1 cm cuvette. *graph in attachemnt* Using the calibration data above for the dye solution, what is the dye concentration in a solution with an absorbance (A) = 0.52 if it was measured in a 1 cm cuvette? Group of answer choices 3.0 x 10-6 M 6.0 x 104 M 2.0 x 10-6 M Not enough information is provided.
4 of 15 Abs 2.0 1.5 1.0 0.5 0.25 0. 0.2 0.4 0.6 Concentration (M) With reference to the UV-Vis calibration curve reported above, calculate the concentration (Molar) of a sample whose Absorbance is 1.0. Report your answer with two significant figures.
The ppm concentration of Pb2+ in a blood sample were measured with Spectrophotometry. 5.00 mL of a blood sample were taken and this sample gave a signal of 0.301 a.u.. Another 5.00 mL of a blood sample were mixed with 0.50 mL og 1.75 ppm Pb2+. Then, this mixture was diluted to 25.00 mL and this diluted mixture gave a signal of 0.406 a.u.. What is the ppm concentration of a blood sample?
After determining the absorbance of several standards of known concentration, the trendline for a calibration curve (AKA a standard curve) plotting absorbance (y-axis) against concentration (M, x-axis) is determined to be y = 4.943x + -0.0001 The absorbance of a solution of unknown concentration is determined to be 0.48. Calculate the concentration of the unknown solution in M. Give your answer to three decimal places.

SEE MORE QUESTIONS

Recommended textbooks for you

Chemistry

ISBN:

9781305957404

Author:

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

Publisher:

Cengage Learning

Chemistry

ISBN:

9781259911156

Author:

Raymond Chang Dr., Jason Overby Professor

Publisher:

McGraw-Hill Education

Principles of Instrumental Analysis

Chemistry

ISBN:

9781305577213

Author:

Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:

Cengage Learning

Chemistry

ISBN:

9781305957404

Author:

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

Publisher:

Cengage Learning

Chemistry

ISBN:

9781259911156

Author:

Raymond Chang Dr., Jason Overby Professor

Publisher:

McGraw-Hill Education

Principles of Instrumental Analysis

Chemistry

ISBN:

9781305577213

Author:

Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:

Cengage Learning

Organic Chemistry

Chemistry

ISBN:

9780078021558

Author:

Janice Gorzynski Smith Dr.

Publisher:

McGraw-Hill Education

Chemistry: Principles and Reactions

Chemistry

ISBN:

9781305079373

Author:

William L. Masterton, Cecile N. Hurley

Publisher:

Cengage Learning

Elementary Principles of Chemical Processes, Bind…

Chemistry

ISBN:

9781118431221

Author:

Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard

Publisher:

WILEY

SEE MORE TEXTBOOKS