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Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left. Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left.   -_____The number of signals in the hydrogen-decoupled <sup>13</sup>C NMR of this compound. -_____The number of signals in the hydrogen-decoupled 13C NMR of this compound.

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Nuclear magnetic resonance spectroscopy provides information about a molecule's carbon-hydrogen framework.

A) True
B) False

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The splitting of signals in the 1H NMR spectrum provides information about the number of neighboring protons of each proton in the compound.

A) True
B) False

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Consider the following structure. Consider the following structure.   If the proton attached to C2 in 1,1,2-tribromopropane is coupled with the protons on C1 (J = 3.6 Hz) and C3 (J = 6.8), the tree diagram of the C2 proton is shown below.  If the proton attached to C2 in 1,1,2-tribromopropane is coupled with the protons on C1 (J = 3.6 Hz) and C3 (J = 6.8), the tree diagram of the C2 proton is shown below. Consider the following structure.   If the proton attached to C2 in 1,1,2-tribromopropane is coupled with the protons on C1 (J = 3.6 Hz) and C3 (J = 6.8), the tree diagram of the C2 proton is shown below.

A) True
B) False

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Which of the following combinations of peaks appears in the 1H NMR spectrum of butane?


A) a triplet and a doublet
B) a triplet and a quartet
C) a triplet and a sextet
D) two singlets

E) All of the above
F) B) and C)

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Which C9H10O compound gives the following 1H NMR spectrum? Which C<sub>9</sub>H<sub>10</sub>O compound gives the following <sup>1</sup>H NMR spectrum?   A)  1 B)  2 C)  3 D)  4


A) 1
B) 2
C) 3
D) 4

E) All of the above
F) None of the above

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Identify the type of coupling that exists between the two protons in the following compound, given that the compound is asymmetrical. ​ Identify the type of coupling that exists between the two protons in the following compound, given that the compound is asymmetrical. ​   A)  Geminal coupling B)  Vicinal coupling C)  Long-range coupling D)  Single-bond coupling


A) Geminal coupling
B) Vicinal coupling
C) Long-range coupling
D) Single-bond coupling

E) B) and D)
F) C) and D)

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What is the splitting of the signal in the 1H NMR spectrum for the methyl protons of ethane?


A) singlet
B) doublet
C) triplet
D) quartet

E) None of the above
F) B) and C)

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Which feature in the 1H NMR spectrum provides information about the electronic environment of the protons in a compound?


A) number of signals
B) integral
C) splitting
D) chemical shift

E) C) and D)
F) A) and B)

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Identify the compound (C8H10) that gives the following 1H NMR spectrum. Identify the compound (C<sub>8</sub>H<sub>10</sub>) that gives the following <sup>1</sup>H NMR spectrum.

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m-xylene (...

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Which of the protons in the following molecule appear furthest downfield in the 1H NMR spectrum? CH3CH2CH2CH2Cl\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{Cl} \quad i \quad\quad\quad ii \quad\quad iii \quad\quad iv


A) i
B) ii
C) iii
D) iv

E) B) and D)
F) None of the above

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For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband hydrogen-decoupled 13C NMR spectra. Enter the numerical value in the blank provided to the left of the structure. -_______ For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband hydrogen-decoupled <sup>13</sup>C NMR spectra. Enter the numerical value in the blank provided to the left of the structure. -_______

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What is the hydrogen deficiency index for a compound with a molecular formula of C10H16O2?


A) 1
B) 2
C) 3
D) 4

E) A) and D)
F) None of the above

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Which C4H9Br compound gives a doublet at approximately 3.3 ppm in the 1H NMR spectrum? Which C<sub>4</sub>H<sub>9</sub>Br compound gives a doublet at approximately 3.3 ppm in the <sup>1</sup>H NMR spectrum?   A)  1 B)  2 C)  3 D)  4


A) 1
B) 2
C) 3
D) 4

E) None of the above
F) A) and C)

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Which of the protons in the following molecule appear furthest downfield in the 1H NMR spectrum? \quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad O \quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad || H3COCH2CH2CH\mathrm{H}_{3} \mathrm{C}-\mathrm{O}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{C}-\mathrm{H} \quad i \quad\quad\quad\quad\quad ii \quad\quad iii \quad\quad\quad iv


A) i
B) ii
C) iii
D) iv

E) A) and B)
F) A) and C)

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Identify the compound (C4H8O) that gives the following 1H NMR spectrum. Identify the compound (C<sub>4</sub>H<sub>8</sub>O) that gives the following <sup>1</sup>H NMR spectrum.

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Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left. Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left.   -_____The number of nonequivalent hydrogen atoms in this compound. -_____The number of nonequivalent hydrogen atoms in this compound.

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Which C8H10 compound gives the following 1H NMR spectrum? Which C<sub>8</sub>H<sub>10</sub> compound gives the following <sup>1</sup>H NMR spectrum?   A)  1 B)  2 C)  3 D)  4


A) 1
B) 2
C) 3
D) 4

E) None of the above
F) C) and D)

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On which factor is chemical shielding not dependent?


A) Hybridization of adjacent atoms
B) Electronegativity of nearby atoms
C) Karplus curve to plot dihedral angles
D) Magnetic induction within an adjacent pi bond

E) A) and C)
F) B) and C)

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Which of the following is not true regarding 1H NMR spectroscopy?


A) a "downfield" peak appears at a lower value of δ
B) on a 300 MHz instrument, a proton that adsorbs irradiation at a frequency 900 Hz higher than the adsorption of TMS appears at δ 3 ppm.
C) δ for a particular proton is independent of the magnetic field strength of the instrument used.
D) "deshielding" leads to peaks at higher values of δ

E) A) and D)
F) A) and B)

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