A student prepared a series of starch standards using the iodine method and measured the absorbance at 590 nm. She obtained thefollowing data.Calibration DataStarch (ng)Absorbance0.000400.078800.1801200.3221600.3762000.511A starch sample, treated in the same fashion, had an absorbance of 0.378. How many nanograms of starch are present in her sample?Enter your answer as an integer (NO decimal places or decimal point) with no units of measure.Answer:

In optics, absorbance or decadic absorbance is defined by the common logarithm of the ratio of…

Answered: A student prepared a series of starch…

A student prepared a series of starch standards using the iodine method and measured the absorbance at 590 nm. She obtained the following data.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.1QAP

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Spectroanalytical Methods

Spectroanalytical methods measure the wavelength and intensity of radiations that are either emitted or absorbed by a molecular or atomic species. These methods are useful for evaluating the electronic or atomic arrangement of the molecules of a given analyte.

Question

A student prepared a series of starch standards using the iodine method and measured the absorbance at 590 nm. She obtained the
following data.
Calibration Data
Starch (ng)
Absorbance
0.000
40
0.078
80
0.180
120
0.322
160
0.376
200
0.511
A starch sample, treated in the same fashion, had an absorbance of 0.378. How many nanograms of starch are present in her sample?
Enter your answer as an integer (NO decimal places or decimal point) with no units of measure.
Answer:

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