Principles of Instrumental Analysis, 6th Edition
6th Edition
ISBN: 9788131525579
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cenage Learning
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Question
Chapter 15, Problem 15.9QAP
Interpretation Introduction
Interpretation:
The mass in milligrams of quinine in the tablet should be determined.
Concept introduction:
The amount of quinine is the product of concentration of quinine and the ratio of the fluorescent intensity of the sample and the fluorescent intensity of the dilute sample.
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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 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
Quinine in a 1.553-g antimalarial tablet was dissolved in sufficient 0.10 M HCl to give 250 mL of solution.A 10.00-mL aliquot was then diluted to 50.00 mL with the acid. The fluorescence intensity for the dilutedsample at 347.5 nm provided a reading of 196 on an arbitrary scale. A standard 100-ppm quinine solutionregistered 125 when measured under conditions identical to those for the diluted sample. Calculate the massin milligrams of quinine in the tablet.
Chapter 15 Solutions
Principles of Instrumental Analysis, 6th Edition
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