Concept explainers
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(a)
Interpretation:
The IUPAC name of the given compound is to be determined.
Concept introduction:
When assigning priorities to substituents, the atom having the greater
When the fourth priority substituent is pointing away (it is attached by a dash bond) and the first, second, and third priority substituents are arranged clockwise, the configuration is R.
When the fourth priority substituent is pointing away (it is attached by a dash bond) and the first, second, and third priority substituents are arranged counterclockwise, the configuration is S.
If the fourth priority substituent is attached by a wedge bond, then the clockwise or counterclockwise arrangement of the first, second, and third priority substituents is determined, and that arrangement is reversed before assigning R or S.
If the fourth priority substituent is in the plane of the page, then it is switched with the substituent that points away. Then the clockwise or counterclockwise arrangement of the first, second, and third priority substituents is determined, and that arrangement is reversed before assigning R or S.
When writing the IPUAC name, the R or S designation is written in parenthesis for each asymmetric carbon atom, and hyphens are used to separate those designations from the rest of the IUPAC name.
(b)
Interpretation:
The IUPAC name of the given compound is to be determined.
Concept introduction:
In a Fischer projection, the vertical bonds point away from the observer while the horizontal ones point towards the observer.
If the fourth priority group attached to a chiral center is on a vertical bond, then the configuration of that chiral center is decided by the clockwise or counterclockwise direction of the groups having first, second, and third priority.
If the fourth priority group attached to a chiral center is on a horizontal bond, then the configuration of that chiral center is reversed as compared to the one shown by the clockwise or counterclockwise direction of the groups having first, second, and third priority.
When assigning priorities to substituents, the atom having the greater atomic number has the higher priority.
In case of comparison between isotopes, the one having the greater atomic mass gets the higher priority.
When writing the IPUAC name, the R or S designation is written in parenthesis for each asymmetric carbon atom, and hyphens are used to separate those designations from the rest of the IUPAC name.
(c)
Interpretation:
The IUPAC name of the given compound is to be determined.
Concept introduction:
When assigning priorities to substituents, the atom having the greater atomic number has the higher priority. In case of comparison between isotopes, the one having the greater atomic mass gets the higher priority.
When the fourth priority substituent is pointing away (it is attached by a dash bond) and the first, second, and third priority substituents are arranged clockwise, the configuration is R.
When the fourth priority substituent is pointing away (it is attached by a dash bond) and the first, second, and third priority substituents are arranged counterclockwise, the configuration is S.
If the fourth priority substituent is attached by a wedge bond, then the clockwise or counterclockwise arrangement of the first, second, and third priority substituents is determined, and that arrangement is reversed before assigning R or S.
If the fourth priority substituent is in the plane of the page, then it is switched with the substituent that points away. Then the clockwise or counterclockwise arrangement of the first, second, and third priority substituents is determined, and that arrangement is reversed before assigning R or S.
When writing the IPUAC name, the R or S designation is written in parenthesis for each asymmetric carbon atom, and hyphens are used to separate those designations from the rest of the IUPAC name.
(d)
Interpretation:
The IUPAC name of the given compound is to be determined.
Concept introduction:
In a Fischer projection, the vertical bonds point away from the observer while the horizontal ones point towards the observer.
If the fourth priority group attached to a chiral center is on a vertical bond, then the configuration of that chiral center is decided by the clockwise or counterclockwise direction of the groups having first, second, and third priority.
If the fourth priority group attached to a chiral center is on a horizontal bond, then the configuration of that chiral center is reversed as compared to the one shown by the clockwise or counterclockwise direction of the groups having first, second, and third priority.
When assigning priorities to substituents, the atom having the greater atomic number has the higher priority.
In case of comparison between isotopes, the one having the greater atomic mass gets the higher priority.
When writing the IPUAC name, the R or S designation is written in parenthesis for each asymmetric carbon atom, and hyphens are used to separate those designations from the rest of the IUPAC name.
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Chapter C Solutions
Get Ready for Organic Chemistry
- d. In Figure 4, each stationary phase shows some negative correlation between plate count and retention factor. In other words, as k' increases, N decreases. Explain this relationship between k' and N. Plate Count (N) 4000 3500 2500 2000 1500 1000 Figure 4. Column efficiency (N) vs retention factor (k') for 22 nonionizable solutes on FMS (red), PGC (black), and COZ (green). 3000 Eluent compositions (acetonitrile/water, A/W) were adjusted to obtain k' less than 15, which was achieved for most solutes as follows: FMS (30/70 A/W), PGC (60/40), COZ (80/20). Slightly different compositions were used for the most highly retained solutes. All columns were 50 mm × 4.6 mm id and packed with 5 um particles, except for COZ, which was packed with 3 um particles. All other chromatographic conditions were constant: column length 5 cm, column j.§. 4.6 mm, flow rate 2 mL/min, column temperature 40 °C, and injection volume 0.5 μL Log(k'x/K'ethylbenzene) FMS 1.5 1.0 0.5 0.0 ཐྭ ཋ ཤྩ བྷྲ ; 500 0 5 10…arrow_forwardf. Predict how the van Deemter curve in Figure 7 would change if the temperature were raised from 40 °C to 55 °C. Figure 7. van Desmter curves in reduced coordinates for four nitroalkane homologues (nitropropane, black; nitrobutane, red; nitropentane, blue; and nitrohexane, green) separated on the FMS phase. Chromatographic conditions: column dimensions 50 mm × 4.6 mm id, eluent 30/70 ACN/water, flow rates 0.2-5.0 mL/min, injection volume 0.5 and column temperature 40 °C. No corrections to the plate heights have been made to account for extracolumn dispersion. Reduced Plate Height (h) ° 20 40 60 Reduced Velocity (v) 8. (2) A water sample is analyzed for traces of benzene using headspace analysis. The sample and standard are spiked with a fixed amount of toluene as an internal standard. The following data are obtained: Ppb benzene Peak area benzene Peak area toluene 10.0 252 376 Sample 533 368 What is the concentration of benzene in the sample?arrow_forwardLiquid chromatography has been used to track the concentration of remdesivir (a broad-spectrum antiviral drug, structure shown at right) in COVID patients undergoing experimental treatments. Intensity The authors provide the following details regarding standard solutions preparation: HN CN HO OH NH2 Remdesivir (RDV) stock solution (5000 µg/mL) was prepared by dissolving RDV drug powder using the mixture of DMSO: MeOH (30:70 v/v). The RDV working standard solutions for calibration and quality controls were prepared using methanol in concentrations of 100, 10, 1, 0.1, 0.01 µg/mL. 1, 2.5, 5, 7.5, 10, 25, 50, 75, 100, 250, 500, 1000, and 5000 ng/mL sample solutions were prepared freshly by spiking calibration standard solutions into the blank human plasma samples for method calibration. a) What type of calibration method is being described? Why do you think the authors chose this method as opposed to another? b) Based on the details provided in part a, describe an appropriate method blank…arrow_forward
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Introductory Chemistry: An Active Learning Approa...ChemistryISBN:9781305079250Author:Mark S. Cracolice, Ed PetersPublisher:Cengage Learning