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At what approximate positions might the following compounds show IR absorptions?
a)
Interpretation:
The approximate absorption frequency has to be given for compound.
Concept introduction:
Spectroscopy: It is study of the interaction of matter and electromagnetic radiation, a continuum of different types of electromagnetic radiation each associated with a particular energy range makes up the electromagnetic spectrum.
IR frequency (cm-1): It is the number of wave crests that pass by a given point in one second frequency has units of hertz (Hz).
Stretch vibrations: It is a vibration occurring along the line of the bond a stretching vibration changes the bond length.
Bending vibrations: It is a vibration that does not occur along the line of the bond, bending vibration changes the bond angle.
Answer to Problem 33AP
The IR absorptions values at 1450-1600 cm-1 is for carbon double bond carbon stretching frequency, 3030 cm-1 is for aromatic carbon hydrogen stretching frequency, 1710-1760 cm-1 is for acid carbonyl frequency and 2500-3100 cm-1 is for acid hydroxyl frequency.
Explanation of Solution
Given information:
The approximate absorption frequency for the given compound,
The IR absorptions values at 1450-1600 cm-1 is for carbon double bond carbon stretching frequency, 3030 cm-1 is for aromatic carbon hydrogen stretching frequency, 1710-1760 cm-1 is for acid carbonyl frequency and 2500-3100 cm-1 is for acid hydroxyl frequency.
Therefore, the approximate absorption frequency for the given compound is shown below,
The approximate absorption frequency is given for compound.
b)
Interpretation:
The approximate absorption frequency has to be given for compound.
Concept introduction:
Spectroscopy: It is study of the interaction of matter and electromagnetic radiation, a continuum of different types of electromagnetic radiation each associated with a particular energy range makes up the electromagnetic spectrum.
IR frequency (cm-1): It is the number of wave crests that pass by a given point in one second frequency has units of hertz (Hz).
Stretch vibrations: It is a vibration occurring along the line of the bond a stretching vibration changes the bond length.
Bending vibrations: It is a vibration that does not occur along the line of the bond, bending vibration changes the bond angle.
Answer to Problem 33AP
The IR absorptions values at 1450-1600 cm-1 is for carbon double bond carbon stretching frequency, 3030 cm-1 is for aromatic carbon hydrogen stretching frequency, 1710-1760 cm-1 is for acid carbonyl frequency and 2500-3100 cm-1 is for acid hydroxyl frequency.
Explanation of Solution
Given information:
The approximate absorption frequency for the given compound,
The IR absorptions values at 1450-1600 cm-1 is for carbon double bond carbon stretching frequency, 3030 cm-1 is for aromatic carbon hydrogen stretching frequency, 1710-1760 cm-1 is for acid carbonyl frequency and 2500-3100 cm-1 is for acid hydroxyl frequency.
Therefore, the approximate absorption frequency for the given compound is shown below,
The difference between given pairs of isomers is explained by using infrared spectroscopy.
c)
Interpretation:
The difference between given pairs of isomer has to be explained by using infrared spectroscopy.
Concept introduction:
Spectroscopy: It is study of the interaction of matter and electromagnetic radiation, a continuum of different types of electromagnetic radiation each associated with a particular energy range makes up the electromagnetic spectrum.
IR frequency (cm-1): It is the number of wave crests that pass by a given point in one second frequency has units of hertz (Hz).
Stretch vibrations: It is a vibration occurring along the line of the bond a stretching vibration changes the bond length.
Bending vibrations: It is a vibration that does not occur along the line of the bond, bending vibration changes the bond angle.
Answer to Problem 33AP
The IR absorptions values at 1450-1600 cm-1 is for carbon double bond carbon stretching frequency, 3030 cm-1 is for aromatic carbon hydrogen stretching frequency, 2210-2260 cm-1 is for acid carbonyl frequency and 3400-3650 cm-1 is for acid hydroxyl frequency.
Explanation of Solution
Given information:
The approximate absorption frequency for the given compound,
The IR absorptions values at 1450-1600 cm-1 is for carbon double bond carbon stretching frequency, 3030 cm-1 is for aromatic carbon hydrogen stretching frequency, 2210-2260 cm-1 is for acid carbonyl frequency and 3400-3650 cm-1 is for acid hydroxyl frequency.
Therefore, the approximate absorption frequency for the given compound is shown below,
The difference between given pairs of isomers is explained by using infrared spectroscopy.
d)
Interpretation:
The difference between given pairs of isomer has to be explained by using infrared spectroscopy.
Concept introduction:
Spectroscopy: It is study of the interaction of matter and electromagnetic radiation, a continuum of different types of electromagnetic radiation each associated with a particular energy range makes up the electromagnetic spectrum.
IR frequency (cm-1): It is the number of wave crests that pass by a given point in one second frequency has units of hertz (Hz).
Stretch vibrations: It is a vibration occurring along the line of the bond a stretching vibration changes the bond length.
Bending vibrations: It is a vibration that does not occur along the line of the bond, bending vibration changes the bond angle.
Answer to Problem 33AP
The IR absorptions values at 1640-1680 cm-1 is for carbon double bond carbon stretching frequency, 3020-3100 cm-1 is for vinylic carbon hydrogen stretching frequency and 1715 cm-1 is for acid hydroxyl frequency.
Explanation of Solution
Given information:
The approximate absorption frequency for the given compound,
The IR absorptions values at 1640-1680 cm-1 is for carbon double bond carbon stretching frequency, 3020-3100 cm-1 is for vinylic carbon hydrogen stretching frequency and 1715 cm-1 is for acid hydroxyl frequency.
Therefore, the approximate absorption frequency for the given compound is shown below,
The difference between given pairs of isomers is explained by using infrared spectroscopy.
e)
Interpretation:
The difference between given pairs of isomer has to be explained by using infrared spectroscopy.
Concept introduction:
Spectroscopy: It is study of the interaction of matter and electromagnetic radiation, a continuum of different types of electromagnetic radiation each associated with a particular energy range makes up the electromagnetic spectrum.
IR frequency (cm-1): It is the number of wave crests that pass by a given point in one second frequency has units of hertz (Hz).
Stretch vibrations: It is a vibration occurring along the line of the bond a stretching vibration changes the bond length.
Bending vibrations: It is a vibration that does not occur along the line of the bond, bending vibration changes the bond angle.
Answer to Problem 33AP
The IR absorptions values at 1715 cm-1 is for carbonyl (ketone) stretching frequency and 1735 cm-1 is for carbonyl ester frequency.
Explanation of Solution
Given information:
The approximate absorption frequency for the given compound,
The IR absorptions values at 1715 cm-1 is for carbonyl (ketone) stretching frequency and 1735 cm-1 is for carbonyl ester frequency.
Therefore, the approximate absorption frequency for the given compound is shown below,
The difference between given pairs of isomers is explained by using infrared spectroscopy.
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Chapter 12 Solutions
Bundle: Organic Chemistry, Loose-leaf Version, 9th + LMS Integrated for OWLv2, 4 terms (24 months) Printed Access Card
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