The concentration of glucose in an aqueous solution can be determined by oxidation with ferricyanide ion, Fe(CN)6^3–. The absorbance of the ferricyanide ion measured at 420 nm increases as the concentration of glucose increases. TT[Glucose], mg / mL5.00010.00Absorbance0.1320.29020.000.49830.000.64240.000.750a.Using the method of least-squares, give the equation of the best straight line through the points.b. Calculate the concentration of an unknown solution that gave an absorbance of 0.440.C.Give the correlation coefficient R and tell whether it is a good fit line or not.

a) In the given table, the absorbance data of ferricyanide ion is given on varying the concentration…

[Glucose), mg / mL | Absorbance 0.132 5.000 10.00 20.00 30.00 0.290 0.498 0.642 40.00 0.750 a. Using the method of least-squares, give the equation of the best straight line through the points. b. Calculate the concentration of an unknown solution that gave an absorbance of 0.440. c. Give the correlation coefficient R and tell whether it is a good fit line or not.

[Glucose), mg / mL | Absorbance 0.132 5.000 10.00 20.00 30.00 0.290 0.498 0.642 40.00 0.750 a. Using the method of least-squares, give the equation of the best straight line through the points. b. Calculate the concentration of an unknown solution that gave an absorbance of 0.440. c. Give the correlation coefficient R and tell whether it is a good fit line or not.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.18QAP

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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 0.144. Assuming that the best fit linear line of the standard curve was y=0.04144x+0.01521 (μgmL), calculate the percent protein by mass in the original protein powder.
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