(a)
Interpretation:
The resolution for species B and C from the given data should be determined.
Concept introduction:
The resolution of the column is defined as the separation of two species of the column.
Answer to Problem 26.16QAP
The resolution is
Explanation of Solution
Given:
The expression of resolution of the column is:
Here, the retention time of species
Substitute
Thus, the resolution is
(b)
Interpretation:
The selectivity factor for species B and C from the given data should be determined.
Concept introduction:
The resolution of the column is defined as the separation of two species of the column.
Answer to Problem 26.16QAP
The selectivity factor is
Explanation of Solution
The expression of selectivity factor is:
Here, the non-retained retention time is
Substitute
Thus, the selectivity factor is
(c)
Interpretation:
The length of column necessary to separate B and C species with a resolution of
Concept introduction:
The resolution of the column is defined as the separation of two species of the column.
Answer to Problem 26.16QAP
The length of column necessary to separate the two species with a resolution of
Explanation of Solution
The expression of length of the column is:
Here, the number of plates needed to separate the two species is
The expression of relation of the resolution and number of plates is:
Here, the number of plates needed is
Substitute
Substitute
Thus, the length of column necessary to separate the two species with a resolution of
(d)
Interpretation:
The time required to separate B and C species on the column of part c should be determined.
Concept introduction:
The resolution of the column is defined as the separation of two species of the column.
Answer to Problem 26.16QAP
The time required to separate the two species on the column of part c is
Explanation of Solution
The expression of the relation of time required to separate the two species on the column is:
Here, the given resolution is
Substitute
Thus, the time required to separate the two species on the column of part c is
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Chapter 26 Solutions
Principles of Instrumental Analysis
- From the data in Problem 26-14, calculate for species C and D) (a) the resolution. (b) the length of column necessary to separate the two species with a resolution of 2.5.arrow_forwardSubstances A, B, C and D were found to have retention times of 8.3 min (A), 10.6 min (B), 12.4 min (C) and 13.5 min (D), respectively on an 15.0 cm long column. There was also an unretained species which appeared at 1.5 min. The widths of the peak bases were 0.90 min (A), 1.1 min (B), 1.3 min (C) and 0.80 min (D). Given this information listed above, please choose the most appropriate answer for the six questions listed below for the list of possible answers. Part A Calculate the capacity factor (k') for peak B and peak D. Part B. Calculate the resolution (R) between peaks B and D. Part C. What do the capacity factor and resolution tell you about the separation of peaks B and D on this column? Part D What are the theoretical plate number (N) for peaks Band D? Part E. What is the average plate height (H), based on the information in Part D and the column length listed above? Part F What would be the required length of a column to achieve a Rs of 2.07arrow_forwardTLC 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 valuearrow_forward
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- Substances A and B have retention times of 16.4 and 17.63 min, respectively, on a 30 cm column. An unretained species passes through the column in 1.3 min. The peak width at base for A and B are 1.11 and 1.21 min, respectively. Calculate:arrow_forwardIn color chromatography of plant pigments, what complications would a dried-out column (solvent level is below the top of the silica) introduce to the elution and isolation of pigments?arrow_forwardThe retention times of two compounds A and B are 16.40 and 17.63 minutes. A species that is not retained passes through the column in 1.30 minutes. The peak widths (at the base) for A and B are 1.11 and 1.21 minutes, respectively. Calculate:a) The resolution of the columnb) The resolution between compounds A and Barrow_forward
- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning