* Question Completion Status:QUESTION 6Most analytical machines used in science can either measure absorbance of light, like the spectrophotometers used in BioZ 151and 152 labs, or can measure change in electrical conductance.In order to convert things like absorbance values into concentration data, a linear regression is used.In order to determine nitrite concentration in water samples, nitrite is reacted with several chemicals to produce a purple color. Theabsorbance of the solution is measured from known amounts of nitrite to produce a standard curve to analyze samples.Use the data in the provided table, or from the linked spreadsheet to make a graph and perform a linear regression using treadline.mg/L NO, Absorbance0.10.1830.30.50.70.5420.9141.2981.61In order for this to work, samples must be diluted prior to measurementstandard curve. If a sample underwent a 0.02 dilution, and produce an absorbance value of 0.903, what is the resultantconcentration of NO2 in mg per L? Report your answer to two decimal places.that the concentration falls within the range of theTip: The regression equation will give you the final concentration. The dilution is equal to V1/N2. The question is asking for theinitial concentration.Save All AClick Save and Submit to save and submit. Click Save All Answers to save all answers.ahere to search Amg/L NO3-Absorbance0.0.10.18340.30.5420.50.9140.71.298711.618.6.101112131415161718192021Sheet1

From the given data, the graph is formed as follows: The equation of the graph is y = 1.662 x + 0.037 where y is the absorbance and x is the concentration.At absorbance (y) = 0.903, the value of concentration is calculated as follows: 0.903=1.662x+0.037x=0.521 mg/L NO3- Dilution factor = 0.02 Calculation of initial concentration: Dilution=C1C20.02=0.521 mg/LC2C2=26.05 mg/L Thus the concentration of NO2- is 26.05 mg/L

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QUESTION 6 Most analytical machines used in science can either measure absorbance of light, like the spectrophotometers used in BioZ 151 and 152 labs, or can measure change in electrical conductance. In order to convert things like absorbance values into concentration data, a linear regression is used. In order to determine nitrite concentration in water samples, nitrite is reacted with several chemicals to produce a purple color. The absorbance of the solution is measured from known amounts of nitrite to produce a standard curve to analyze samples. Use the data in the provided table, or from the linked spreadsheet to make a graph and perform a linear regression using treadline. mg/L NO, Absorbance 0.183 0.542 0.914 1.298 1.61 0.1 0.3 0.5 07 In order for this to work, samples must be diluted prior to measurement so that the concentration falls within the range of the standard curve. If a sample underwent a 0.02 dilution, and produce an absorbance value of 0.903, what is the resultant concentration of NO2 in mg per L? Report your answer to two decimal places. Tip: The regression equation will give you the final concentration. The dilution is equal to V1/N2. The question is asking for the initial concentration.

QUESTION 6 Most analytical machines used in science can either measure absorbance of light, like the spectrophotometers used in BioZ 151 and 152 labs, or can measure change in electrical conductance. In order to convert things like absorbance values into concentration data, a linear regression is used. In order to determine nitrite concentration in water samples, nitrite is reacted with several chemicals to produce a purple color. The absorbance of the solution is measured from known amounts of nitrite to produce a standard curve to analyze samples. Use the data in the provided table, or from the linked spreadsheet to make a graph and perform a linear regression using treadline. mg/L NO, Absorbance 0.183 0.542 0.914 1.298 1.61 0.1 0.3 0.5 07 In order for this to work, samples must be diluted prior to measurement so that the concentration falls within the range of the standard curve. If a sample underwent a 0.02 dilution, and produce an absorbance value of 0.903, what is the resultant concentration of NO2 in mg per L? Report your answer to two decimal places. Tip: The regression equation will give you the final concentration. The dilution is equal to V1/N2. The question is asking for the initial concentration.

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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