Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
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Chapter 17, Problem 17.9QAP
Interpretation Introduction
Interpretation:
The equation of the calibration curve should be determined and the concentration of the three unknown samples should be determined.
Concept introduction:
A calibration curve or standard curve is a method used in
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A student wanted to determine the level of lead in amoxicillin powder, so he
transferred 148 mg of the powder to 200 ml volumetric flask and completed
the volume volumetrically, then he transferred 5 ml of the obtained solution to
50 ml volumetric flask and completed the volume properly, and read the
absorbance of the obtained solution on AAS. The reading was 0.48. and the
calibration equation was: "Y =12.25 x- 0.05" (concentration microg./mL).
?"Calculate the content of lead in amoxicillin as "ppm
326.5.a O
605.0 .b O
60.5.c O
17.5.d O
584.7.e O
أخل اختياري
A food supplement is analyzed by Atomic Absorption Spectroscopy to know its Ca content. A 10 ppm standard registers an absorbance of 0.448. A 4.45 g sample is calcined, the ashes are dissolved with 10 mL of acid, and the solution is finally made up to 50 mL; the absorbance reading was 0.325.
How many mg of Ca are in 100 g of the dietary supplement?
A student wanted to
determine the level of lead in
amoxicillin powder, so he
transferred 148 mg of the
powder to 200 ml volumetric
flask and completed the
volume volumetrically, then
he transferred 5 ml of the
obtained solution to 50 ml
volumetric flask and
completed the volume
properly, and read the
absorbance of the obtained
solution on AAS. The reading
was 0.48. and the calibration
equation was: "Y =12.25 x-
0.05" (concentration
microg./mL). Calculate the
content of lead in amoxicillin
as "ppm"?
O a. 326.5
O b. 605.0
Chapter 17 Solutions
Principles of Instrumental Analysis
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