Show how IR spectroscopy can be used to distinguish between the compounds in each of the

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. Integration reveals the number of neighboring hydrogens in a ¹H-NMR spectrum. (11.11)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. Integration reveals the number of neighboring hydrogens in a ¹H-NMR spectrum. (11.11)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A transition between two energy states, E? and E?, can be made to occur using light equal to or greater than the energy difference between E? and E?. (11.2)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A compound with the molecular formula C?H??O could contain a C ? C triple bond, two C = O bonds, or two rings. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A ketone can be distinguished from an aldehyde via ¹³C-NMR spectroscopy. (11.12)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A compound with the molecular formula C?H??O has an index of hydrogen deficiency of 2. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A ¹H-NMR spectrum with an integration ratio of 3 : 1 : 2 could represent a compound with the molecular formula C?H?O. (11.9)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. The collection of absorption peaks in the 1000–400 cm?¹ region of an IR spectrum is unique to a particular compound (i.e., no two compounds will yield the same spectrum in this region). (11.3)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. The area under each peak in a ¹H-NMR spectrum can be determined using a technique known as integration. (11.9)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A carboxylic acid can be distinguished from an aldehyde via ¹H-NMR spectroscopy. (11.10)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A wavenumber, , is directly proportional to frequency. (11.3)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. The methyl carbon of 1-chlorobutane will yield a ¹H-NMR signal that appears as a triplet. (11.11)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A compound with the molecular formula C?H??FN has an index of hydrogen deficiency of 1. (11.4)

Calculate the index of hydrogen deficiency of each compound: (See Examples 11.5, 11.6) (a) Aspirin, C?H?O? (b) Ascorbic acid (vitamin C), C?H?O? (c) Pyridine, C?H?N (d) Urea, CH?N?O (e) Cholesterol, C??H??O (f) Trichloroacetic acid, C?HCl?O?

Compound A, with the molecular formula C?H??, reacts with H?/Ni to give compound B, with the molecular formula C?H??. The IR spectrum of compound A is provided. From this information about compound A tell (See Examples 11.4–11.7)

Compound C, with the molecular formula C?H??, reacts with H?/Ni to give compound D, with the molecular formula C?H?? . The IR spectrum of compound C is provided. From this information about compound C, tell (See Examples 11.4–11.7) (a) Its index of hydrogen deficiency. (b) The number of rings or pi bonds (or both) in compound C. (c) What structural feature(s) would account for compound C’s index of hydrogen deficiency.

Examine the following IR spectrum and the molecular formula of compound E, C?H??O: Tell (See Examples 11.4–11.7) (a) Its index of hydrogen deficiency. (b) The number of rings or pi bonds (or both) in compound E. (c) What one structural feature would account for this index of hydrogen deficiency. (d) What oxygen-containing functional group compound E contains.

Examine the following IR spectrum and the molecular formula of compound F, C?H??N: Tell (See Examples 11.4–11.7) (a) Its index of hydrogen deficiency. (b) The number of rings or pi bonds (or both) in compound F. (c) The nitrogen-containing functional group(s) compound F might contain.

Examine the following IR spectrum and the molecular formula of compound G, C?H??O: Tell (See Examples 11.4–11.7) (a) Its index of hydrogen deficiency. (b) The number of rings or pi bonds (or both) in compound G. (c) What structural features would account for this index of hydrogen deficiency.

Examine the following IR spectrum and the molecular formula of compound H, C?H??O?: Tell (See Examples 11.4–11.7) (a) Its index of hydrogen deficiency. (b) The number of rings or pi bonds (or both) in compound H. (c) The oxygen-containing functional group(s) compound H might contain.

Examine the following IR spectrum and the molecular formula of compound I, C?H?NO: Tell (See Examples 11.4–11.7) (a) Its index of hydrogen deficiency. (b) The number of rings or pi bonds (or both) in compound I. (c) The oxygen- and nitrogen-containing functional group(s) in compound I.

For each pair of compounds that follows, list one major feature that appears in the IR spectrum of one compound, but not the other. In your answer, state what type of bond vibration is responsible for the spectral feature you list, and give its approximate position in the IR spectrum. (See Examples 11.2, 11.3)

Following are an infrared spectrum and a structural formula for methyl salicylate, the fragrant component of oil of wintergreen. On this spectrum, locate the absorption peak(s) due to (See Examples 11.2, 11.3) (a) O ? H stretching of the hydrogen-bonded iOH group (very broad and of medium intensity). (b) C ? H stretching of the aromatic ring (sharp and of weak intensity). (c) C = O stretching of the ester group (sharp and of strong intensity). (d) C = C stretching of the aromatic ring (sharp and of medium intensity).

Determine the number of signals you would expect to see in the ¹H-NMR spectrum of each of the following compounds. (See Example 11.9)

Determine the number of signals you would expect to see in the ¹³C-NMR spectrum of each of the compounds in Problem 11.31. (See Example 11.14)

Following are structural formulas for the constitutional isomers of xylene and three sets of ¹³C-NMR spectra. Assign each constitutional isomer its correct spectrum. (See Example 11.17)

Following is a ¹H-NMR spectrum for compound J, with the molecular formula C?H??. Compound J decolorizes a solution of bromine in carbon tetrachloride. Propose a structural formula for compound J. (See Examples 11.15, 11.16)

Following is a ¹H-NMR spectrum for compound K, with the molecular formula C?H??. Compound K decolorizes a solution of Br? in CCl?. Propose a structural formula for compound K. (See Examples 11.15, 11.16)

Following are the ¹H-NMR spectra of compounds L and M, each with the molecular formula C?H?Cl. Each compound decolorizes a solution of Br? in CCl?. Propose structural formulas for compounds L and M. (See Examples 11.15, 11.16)

Following are the structural formulas of three alcohols with the molecular formula C?H??O and three sets of ¹³C-NMR spectral data. Assign each constitutional isomer to its correct spectral data. (See Example 11.17)

Alcohol N, with the molecular formula C?H??O, undergoes acid-catalyzed dehydration when it is warmed with phosphoric acid, giving compound O, with the molecular formula C?H??, as the major product. A ¹H-NMR spectrum of compound N shows peaks at ???? 0.89 (t, 6H), 1.12 (s, 3H), 1.38 (s, 1H), and 1.48 (q, 4H). The ¹³C-NMR spectrum of compound N shows peaks at ???? 72.98, 33.72, 25.85, and 8.16. Propose structural formulas for compounds N and O. (See Examples 11.15–11.17)

Compound P, C?H??O, does not react with sodium metal and does not discharge the color of Br? in CCl?. The ¹H-NMR spectrum of compound P consists of only two signals: a 12H doublet at ???? 1.1 and a 2H septet at ???? 3.6. Propose a structural formula for compound P. (See Examples 11.15, 11.16)

Propose a structural formula for each haloalkane: (See Examples 11.15, 11.16)

Following are structural formulas for esters (1), (2), and (3) and three ¹H-NMR spectra. Assign each compound its correct spectrum (Q, R, or S) and assign all signals to their corresponding hydrogens. (See Examples 11.15, 11.16)

Compound T, C??H??O? , is insoluble in water, 10% NaOH, and 10% HCl. A ¹H-NMR spectrum of compound T shows signals at ???? 2.55 (s, 6H) and 7.97 (s, 4H). A ¹³C-NMR spectrum of compound T shows four signals. From this information, propose a structural formula for T. (See Examples 11.15–11.17)

Compound U, C??H??O, is used as an antioxidant in many commercial food products, synthetic rubbers, and petroleum products. Propose a structural formula for compound U based on its ¹H-NMR and ¹³C-NMR spectra. (Sees Example 11.15–11.17)

Propose a structural formula for these compounds, each of which contains an aromatic ring: (See Examples 11.15, 11.16)

Compound V, with the molecular formula C?H??O, readily undergoes acid-catalyzed dehydration to give compound W, with the molecular formula C?H??. A ¹H-NMR spectrum of compound V shows signals at ???? 0.91 (t, 3H), 1.78 (m, 2H), 2.26 (s, 1H), 4.55 (t, 1H), and 7.31 (m, 5H). From this information, propose structural formulas for compounds V and W. (See Examples 11.15, 11.16)

Propose a structural formula for each ketone: (See Examples 11.15, 11.16)

Propose a structural formula for compound X, a ketone with the molecular formula C??H??O: (See Examples 11.15, 11.16)

Following is a ¹H-NMR spectrum for compound Y, with the molecular formula C?H??O?. Compound Y undergoes acid-catalyzed dehydration to give compound Z, C?H??O. Propose structural formulas for compounds Y and Z. (See Examples 11.15, 11.16)

Propose a structural formula for compound AA, with the molecular formula C??H??O. Following are its ¹H-NMR and ¹³C-NMR spectra: (See Examples 11.15–11.17)

Propose a structural formula for each carboxylic acid: (See Examples 11.15–11.17)

Following are ¹H-NMR and ¹³C-NMR spectra of compound BB, with the molecular formula C?H??O?. Propose a structural formula for compound BB. (See Examples 11.15–11.17)

Propose a structural formula for each ester: (See Examples 11.15–11.17)

Following are ¹H-NMR and ¹³C-NMR spectra of compound CC, with the molecular formula C??H??NO. Propose a structural formula for this compound. (See Examples 11.15–11.17)

Propose a structural formula for amide DD, with the molecular formula C?H??NO: (See Examples 11.15, 11.16)

Propose a structural formula for the analgesic phenacetin, with molecular formula C??H??NO?, based on its ¹H-NMR spectrum: (See Examples 11.15, 11.16)

Propose a structural formula for compound EE, an oily liquid with the molecular formula C?H?NO?. Compound EE is insoluble in water and aqueous NaOH, but dissolves in 10% HCl. When its solution in HCl is neutralized with NaOH, compound EE is recovered unchanged. A ¹H-NMR spectrum of compound EE shows signals at ???? 3.84 (s, 3H), 4.18 (s, 2H), 7.60 (d, 2H), and 8.70 (d, 2H). (See Examples 11.15, 11.16)

Following is a ¹H-NMR spectrum and a structural formula for anethole, C??H??O, a fragrant natural product obtained from anise. Using the line of integration, determine the number of protons giving rise to each signal. Show that this spectrum is consistent with the structure of anethole. (See Examples 11.15, 11.16)

Propose a structural formula for compound FF, with the molecular formula C?H?O, based on the following IR and ¹H-NMR spectra: (See Examples 11.15, 11.16)

Propose a structural formula for compound GG, with the molecular formula C?H??O? , based on the following IR and ¹H-NMR spectra: (See Examples 11.15, 11.16)

Propose a structural formula for compound HH, with the molecular formula C?H?ClO?, based on the following IR and ¹H-NMR spectra: (See Examples 11.15, 11.16)

Propose a structural formula for compound II, with the molecular formula C?H??O, based on the following IR and ¹H-NMR spectra: (See Examples 11.15, 11.16)

Predict the position of the C = O stretching absorption in acetate ion relative to that in acetic acid:

Following is the IR spectrum of L-tryptophan, a naturally occurring amino acid that is abundant in foods such as turkey: For many years, the ?-tryptophan in turkey was believed to make people drowsy after Thanksgiving dinner. Scientists now know that consuming ?-tryptophan makes one drowsy only if the compound is taken on an empty stomach. Therefore, it is unlikely that one’s Thanksgiving Day turkey is the cause of drowsiness. Notice that ?-tryptophan contains one stereocenter. Its enantiomer, ?-tryptophan, does not occur in nature but can be synthesized in the laboratory. What would the IR spectrum of ?-tryptophan look like?

Discuss whether IR or NMR spectroscopy could be used to distinguish between the following pairs of molecules. Be very specific in describing the spectral data that would allow you to identify each compound. Assume that you do not have the reference spectra of either molecule.

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A weak absorption band in an infrared spectrum can be attributed to, among other things, absorption of infrared light by a low polarity bond. (11.3)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. Wavelength and frequency are directly proportional. That is, as wavelength increases, frequency increases. (11.1)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. IR spectroscopy can be used to distinguish between a terminal alkyne and an internal alkyne. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. The NMR signal of a shielded nucleus appears more upfield than the signal for a deshielded nucleus. (11.7)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. The chemical shift of a nucleus depends on its resonance frequency. (11.7)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. Electromagnetic radiation can be described as a wave, as a particle, and in terms of energy. (11.1)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A set of hydrogens are equivalent if replacing each of them with a halogen results in compounds of the same name. (11.8)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. All atomic nuclei have a spin, which allows them to be analyzed by NMR spcctroscopy. (11.5)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. C ? H stretching vibrations occur at higher wavenumbers than C ? C stretching vibrations. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. The resonance frequency of a nucleus depends on its amount of shielding. (11.6)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. It is not possible to use IR spectroscopy to distinguish between a ketone and a carboxylic acid. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. Resonance is the excitation of a magnetic nucleus in one spin state to a higher spin state. (11.5)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. IR spectroscopy cannot be used to distinguish between an alcohol and an ether. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A compound with an index of hydrogen deficiency of 1 can contain either one ring, one double bond, or one triple bond. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. Infrared spectroscopy measures transitions between electronic energy levels. (11.2)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. A set of hydrogens represented by a doublet indicates that there are two neighboring equivalent hydrogens. (11.11)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. The index of hydrogen deficiency can reveal the possible number of rings, double bonds, or triple bonds in a compound based solely on its molecular formula. (11.4)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. TMS, tetramethylsilane, is a type of solvent used in NMR spectroscopy. (11.7)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. Light of wavelength 400 nm is higher in energy than light of wavelength 600 nm. (11.1)

Answer true or false to the following questions to assess your general knowledge of the concepts in this chapter. If you have difficulty with any of them, you should review the appropriate section in the chapter (shown in parentheses) before attempting the more challenging end-of-chapter problems. IR spectroscopy can be used to distinguish between 1°, 2°, and 3° amines. (11.4)

Which puts out light of higher energy, a green laser pointer or a red laser pointer? (See Example 11.1)

Calculate the energy, in kilocalories per mole of radiation, of a wave with wavelength 2 m. What type of radiant energy is this? (See Example 11.1)

A molecule possesses molecular orbitals that differ in energy by 82 kcal/mol. What wavelength of light would be required to cause a transition between these two energy levels? What region of the electromagnetic spectrum does this energy correspond to? (See Example 11.1)

Show how IR spectroscopy can be used to distinguish between the compounds in each of the following pairs: (See Examples 11.2, 11.3) (a) 1-Butanol and diethyl ether (b) Butanoic acid and 1-butanol (c) Butanoic acid and 2-butanone (d) Butanal and 1-butene (e) 2-Butanone and 2-butanol (f) Butane and 2-butene