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 9, Problem 9.16QAP
Interpretation Introduction
Interpretation:
The lead concentration in parts per million (ppm) in a canned orange juice sample needs to be determined.
Concept introduction:
Spectral lines are lines which help in identifying the atoms and molecules. These are a result of absorption or emission of light in a comparatively narrower frequency range compared to the frequencies nearby.
In a defined space, the amount of a substance is its concentration. A substance’s capacity to absorb specific
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1. A solution that absorbs radiation with a λmax at 475nm is placed within a UV visible spectrophotometer. An absorbance of 0.82 is recorded. Calculate the percentage of the incident light that is being absorbed.
True or False
1. Photodiode arrays are devices within the instrument that help amplify the signal of a sample.
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3. Organic compounds are normally analyzed in atomic spectroscopy despite their small electronic transition range.
The measurement of Li in brine (salt water) is used by geochemists to help determine the origin of this fluid in oil fields. Flame atomic absorption of Li is subject to interference by other elements. Atomic absorption of analysis of replicate sample of Li in a brine sample gave results in the table.
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b. Suggest a reason for the increasing apparent concentration of Li from sample 1 to 3
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Chapter 9 Solutions
Principles of Instrumental Analysis
Ch. 9 - Prob. 9.1QAPCh. 9 - Prob. 9.2QAPCh. 9 - Why is an electrothermal atomizer more sensitive...Ch. 9 - Prob. 9.4QAPCh. 9 - Prob. 9.5QAPCh. 9 - Prob. 9.6QAPCh. 9 - Prob. 9.7QAPCh. 9 - Prob. 9.8QAPCh. 9 - Prob. 9.9QAPCh. 9 - Prob. 9.10QAP
Ch. 9 - Prob. 9.11QAPCh. 9 - Prob. 9.12QAPCh. 9 - Prob. 9.13QAPCh. 9 - Prob. 9.14QAPCh. 9 - Prob. 9.15QAPCh. 9 - Prob. 9.16QAPCh. 9 - Prob. 9.17QAPCh. 9 - In the concentration range of 1 to 100 g/mL P,...Ch. 9 - Prob. 9.19QAPCh. 9 - Prob. 9.20QAPCh. 9 - Prob. 9.21QAPCh. 9 - The chromium in an aqueous sample was determined...Ch. 9 - Prob. 9.23QAP
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