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 28, Problem 28.22QAP
Interpretation Introduction
(a)
Interpretation:
The retention factor is to be stated.
Concept introduction:
The retention factor is defined as the ratio of distance moved by the solute and the distance moved by the solvent in the column.
Interpretation Introduction
(b)
Interpretation:
The solvent composition is to be stated.
Concept introduction:
The solvent contains the chloroform and hexane. The mole fraction gives the composition of the solvent.
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3.) The following Beer's Law calibration plot was collected at 391.9 nm using the five mixtures listed above. The trendline equation was y = 4617.1x. A saturated solution of lead(II) chromate had an absorbance of 0.0025.
Calculate its solubility, in molarity.
Molar Solubility of PbCrO4: x 107 M
ABSORBANCE VS CHROMATE CONCENTRATION AT 391.9 NM
1.40
1.20
y = 4617.1x
R-0.9972
1.00
0.80
0.60
0.40
0.20
0.00 C
0.00005
0.0001
0.00015
0.0002
0.00025
0.0003
Chromate concentration (mol.L)
TLC was used to compare the solubility of two compounds A and B in a solvent system (acetic acid, methanol, H2O). The distances that solvent has moved in the silica gel TLC was 12 cm. and for the compounds were 2 and 8 cm respectively. (a) Calculate the Rf values and which compound is more soluble and which one is more polar. (b) What are the factors affecting the Rf value
A 36.0 mg sample of an organic compound (molar mass = 84.0 g/mol) is dissolved in 10.0 mL of water. This aqueous solution is extracted with 5.0 mL of hexane. Separation and analysis of the aqueous phase shows that it now contains 12.0 mg of the organic compound. Calculate the partition coefficient for the compound between hexane and water (Kphexane/water). Your answer should reflect the proper number of significant figures.
Chapter 28 Solutions
Principles of Instrumental Analysis
Ch. 28 - Prob. 28.1QAPCh. 28 - Prob. 28.2QAPCh. 28 - Prob. 28.3QAPCh. 28 - How can the selectivity factor be manipulated in...Ch. 28 - Prob. 28.5QAPCh. 28 - Prob. 28.6QAPCh. 28 - Prob. 28.7QAPCh. 28 - Prob. 28.8QAPCh. 28 - Prob. 28.9QAPCh. 28 - Prob. 28.10QAP
Ch. 28 - Prob. 28.11QAPCh. 28 - Prob. 28.12QAPCh. 28 - Prob. 28.13QAPCh. 28 - Prob. 28.14QAPCh. 28 - Prob. 28.15QAPCh. 28 - Prob. 28.16QAPCh. 28 - Mass spectrometry is an extremely versatile...Ch. 28 - Prob. 28.18QAPCh. 28 - Prob. 28.19QAPCh. 28 - Two components in an HPLC separation have...Ch. 28 - Prob. 28.21QAPCh. 28 - Prob. 28.22QAPCh. 28 - Prob. 28.23QAP
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