Question 1

Which of the following statements about13C NMR isnot true?

Accepted Answer

A)   In13C proton-decoupled NMR spectra, all peaks are singlets.
B)   13C NMR easily differentiates between the different hybridized carbons (sp3,sp2, andsp hybridized carbons) .
C)   13C NMR chemical shifts occur over a greater range than1H NMR chemical shifts.
D)   13C NMR spectra display peaks for only carbons that bear hydrogen atoms.E) B) and C)
F) A) and D)

Question 2

You are given a bottle of an organic liquid and told it must be either cyclohexane or 1-hexene. Which of the following statements is (are)  true about these two compounds? -1 but cyclohexane will not. B)  Statements (The two compounds can be differentiated by their mass spectra because they will have molecular ions at different masses) , (1-Hexene will show an absorption at 1650 cm-1 but cyclohexane will not) , and (Both cyclohexane and 1- hexene will show C-H absorptions at about 2950 cm-1)  are all true. C)  Statements (1-Hexene will show an absorption at 1650 cm-1 but cyclohexane will not)  and (Both cyclohexane and 1-hexene will show C-H absorptions at about 2950 cm-1)  are both true. D)  The two compounds can be differentiated by their mass spectra because they will have molecular ion peaks at different m/z. E)  Both cyclohexane and 1-hexene will show C-H absorptions at about 2950 cm-1." class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1-Hexene will show an absorption at 1650 cm-1 but cyclohexane will not.
B)   Statements (The two compounds can be differentiated by their mass spectra because they will have molecular ions at different masses) , (1-Hexene will show an absorption at 1650 cm-1 but cyclohexane will not) , and (Both cyclohexane and 1- hexene will show C-H absorptions at about 2950 cm-1)  are all true.
C)   Statements (1-Hexene will show an absorption at 1650 cm-1 but cyclohexane will not)  and (Both cyclohexane and 1-hexene will show C-H absorptions at about 2950 cm-1)  are both true.
D)   The two compounds can be differentiated by their mass spectra because they will have molecular ion peaks at different m/z.
E)   Both cyclohexane and 1-hexene will show C-H absorptions at about 2950 cm-1.F) B) and D)
G) A) and B) C

Question 3

Which of the following statements is (are)  true about a compound that has molecular ion peaks in its mass spectrum at mass 170 and 172 and shows prominent peaks in its IR spectrum at 3150-3000 and 1600 cm-1?

Accepted Answer

A)   Both (The compound is not pure)  and (The compound contains a halogen)  are true statements.
B)   Both (The compound is not pure)  and (The compound contains an OH group and Csp3-H hybridized bonds)  are true statements.
C)   The compound contains an OH group and Csp3-H hybridized bonds.
D)   The compound contains a halogen.
E)   The compound is not pure.F) A) and B)
G) A) and E)

Question 4

Which of the following statements is (are)  true about a compound that has a molecular ion peak in its mass spectrum at mass 104 and shows prominent peaks in its IR spectrum at 3200-2850 cm-1?

Accepted Answer

A)   The compound contains an OH group and Csp3-H hybridized bonds.
B)   Both (The compound has a molecular mass of 104)  and (The compound contains a C=O group and Csp3-H hybridized bonds)  are true statements.
C)   The compound contains a C=O group and Csp3-H hybridized bonds.
D)   Both (The compound has a molecular mass of 104)  and (The compound contains an OH group and Csp3-H hybridized bonds)  are true statements.
E)   The compound has a molecular mass of 104.F) A) and D)
G) C) and D)

Question 5

Which of the following statements is (are)  true about a compound that has a molecular ion peak in its mass spectrum at mass 94 and shows prominent peaks in its IR spectrum at 3600-3200 and 1600 cm-1?

Accepted Answer

A)   Both (The compound has a molecular mass of 94)  and (The compound contains an OH group and a benzene ring)  are true statements.
B)   Both (The compound has a molecular mass of 94)  and (The compound contains a C=O group and Csp3-H hybridized bonds)  are true statements.
C)   The compound has a molecular mass of 94.
D)   The compound contains an OH group and a benzene ring.
E)   The compound contains a C=O group and Csp3-H hybridized bonds.F) B) and D)
G) C) and D)

Question 6

A compoundX has a molecular ion peak in its mass spectrum at m/z 136. What information does this tell us aboutX?

Accepted Answer

A)   X has a molecular mass of 136.
B)   Statements (X has a molecular mass of 136) , (The molecular formula forX is C8H8O2) , and (The empirical formula forX is C4H4O)  are all true.
C)   Both A (X has a molecular mass of 136)  and B (The molecular formula forX is C8H8O2)  are true.
D)   The molecular formula forX is C8H8O2.
E)   The empirical formula forX is C4H4O.F) A) and C)
G) C) and E)

Question 7

Examine the IR below and classify the compound.

Accepted Answer

A)   Amine
B)   Carbocylic acid
C)   Ketone
D)   Alcohol
E)   AreneF) C) and E)
G) A) and B)

Question 8

Which of the following statements is (are)  accurate about the IR spectrum of compounds I, II, and III below? -1. B)  Both (CompoundI shows absorptions at 2950 and 1700 cm-1)  and (CompoundII shows absorptions at 3200-3600 and 1650 cm-1)  are true. C)  CompoundIII shows absorptions at 3200-3600 and 2950 cm-1. D)  CompoundII shows absorptions at 3200-3600 and 1650 cm-1." class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   CompoundI shows absorptions at 2950 and 1700 cm-1.
B)   Both (CompoundI shows absorptions at 2950 and 1700 cm-1)  and (CompoundII shows absorptions at 3200-3600 and 1650 cm-1)  are true.
C)   CompoundIII shows absorptions at 3200-3600 and 2950 cm-1.
D)   CompoundII shows absorptions at 3200-3600 and 1650 cm-1.E) A) and B)
F) A) and D) B

Question 9

How could spectroscopy be used to distinguish between the following compounds? -1 in its IR spectrum.  B)  Compound B has a peak at 3200-3500 cm-1 in its IR spectrum. C)  Compound A has a triplet in its1H NMR spectrum at 1.0 ppm. D)  Compound A has a peak in its IR spectrum at 2900 cm-1." class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   Compound A has a triplet in its 1H NMR spectrum at 1.0 ppm and compound B has a peak at 3200-3500 cm-1 in its IR spectrum. 
B)   Compound B has a peak at 3200-3500 cm-1 in its IR spectrum.
C)   Compound A has a triplet in its1H NMR spectrum at 1.0 ppm.
D)   Compound A has a peak in its IR spectrum at 2900 cm-1.E) All of the above
F) B) and D)

Question 10

Consider the three organic compounds drawn below. Which of the following statements is (are)  true about the IR spectra of I, II, and III? -1 and 2250 cm-1. B)  Statements (I shows strong absorptions at 2950 cm-1 and 1700 cm-1)  and (III shows strong absorptions at 2950 cm-1 and 3200-3600 cm-1)  are true. C)  III shows strong absorptions at 2950 cm-1 and 3200-3600 cm-1. D)  I shows strong absorptions at 2950 cm-1 and 1700 cm-1." class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   II shows strong absorptions at 2950 cm-1 and 2250 cm-1.
B)   Statements (I shows strong absorptions at 2950 cm-1 and 1700 cm-1)  and (III shows strong absorptions at 2950 cm-1 and 3200-3600 cm-1)  are true.
C)   III shows strong absorptions at 2950 cm-1 and 3200-3600 cm-1.
D)   I shows strong absorptions at 2950 cm-1 and 1700 cm-1.E) B) and D)
F) A) and C)

Question 11

Which of the following statement(s)  is (are)  true about a compound that has a molecular ion peak in its mass spectrum at mass 69 and shows a prominent peak in its IR spectrum at 2250 cm-1?

Accepted Answer

A)   Both (The compound has a molecular mass of 70)  and (The compound contains a cyano or alkyne group)  are true statements.
B)   The compound contains a cyano or alkyne group.
C)   The compound contains a C=O group.
D)   Both (The compound has a molecular mass of 70)  and (The compound contains a C=O group)  are true statements.
E)   The compound has a molecular mass of 70.F) A) and E)
G) A) and D) B

Question 12

Which of the following statements is (are)  true about the IR spectrum of the compound drawn below? -1 and 1650 cm-1. B)  It shows absorptions at 3000-3150 cm-1 and 1720 cm-1. C)  It shows absorptions at 3000-2850 cm-1 and 2150 cm-1. D)  It shows absorptions at 2250 cm-1 and 1720 cm-1. E)  Both statements (It shows absorptions at 3000-2850 cm-1 and 2250 cm-1)  and (It shows absorptions at 2250 cm-1 and 1720 cm-1)  are true." class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   It shows absorptions at 2250 cm-1 and 1650 cm-1.
B)   It shows absorptions at 3000-3150 cm-1 and 1720 cm-1.
C)   It shows absorptions at 3000-2850 cm-1 and 2150 cm-1.
D)   It shows absorptions at 2250 cm-1 and 1720 cm-1.
E)   Both statements (It shows absorptions at 3000-2850 cm-1 and 2250 cm-1)  and (It shows absorptions at 2250 cm-1 and 1720 cm-1)  are true.F) A) and B)
G) B) and D)

Exam 29: Spectroscopy : Mass Spectrometry, Infrared Spectroscopy, and Nuclear Magnetic Resonance Spectroscopy

Which of the following statements about¹³C NMR isnot true?

Correct Answer
verified

You are given a bottle of an organic liquid and told it must be either cyclohexane or 1-hexene. Which of the following statements is (are) true about these two compounds?

Correct Answer
verified
C

Which of the following statements is (are) true about a compound that has molecular ion peaks in its mass spectrum at mass 170 and 172 and shows prominent peaks in its IR spectrum at 3150-3000 and 1600 cm^-1?

Correct Answer
verified

Which of the following statements is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 104 and shows prominent peaks in its IR spectrum at 3200-2850 cm^-1?

Correct Answer
verified

Which of the following statements is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 94 and shows prominent peaks in its IR spectrum at 3600-3200 and 1600 cm^-1?

Correct Answer
verified

A compoundX has a molecular ion peak in its mass spectrum at m/z 136. What information does this tell us aboutX?

Correct Answer
verified

Examine the IR below and classify the compound.

Correct Answer
verified

Which of the following statements is (are) accurate about the IR spectrum of compounds I, II, and III below?

Correct Answer
verified
B

How could spectroscopy be used to distinguish between the following compounds?

Correct Answer
verified

Consider the three organic compounds drawn below. Which of the following statements is (are) true about the IR spectra of I, II, and III?

Correct Answer
verified

Which of the following statement(s) is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 69 and shows a prominent peak in its IR spectrum at 2250 cm^-1?

Correct Answer
verified
B

Which of the following statements is (are) true about the IR spectrum of the compound drawn below?

Correct Answer
verified

Exam 29: Spectroscopy : Mass Spectrometry, Infrared Spectroscopy, and Nuclear Magnetic Resonance Spectroscopy

Which of the following statements about13C NMR isnot true?

Correct AnswerverifiedShow Answer

You are given a bottle of an organic liquid and told it must be either cyclohexane or 1-hexene. Which of the following statements is (are) true about these two compounds?

Correct AnswerverifiedC

Which of the following statements is (are) true about a compound that has molecular ion peaks in its mass spectrum at mass 170 and 172 and shows prominent peaks in its IR spectrum at 3150-3000 and 1600 cm-1?

Correct AnswerverifiedShow Answer

Which of the following statements is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 104 and shows prominent peaks in its IR spectrum at 3200-2850 cm-1?

Correct AnswerverifiedShow Answer

Which of the following statements is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 94 and shows prominent peaks in its IR spectrum at 3600-3200 and 1600 cm-1?

Correct AnswerverifiedShow Answer

A compoundX has a molecular ion peak in its mass spectrum at m/z 136. What information does this tell us aboutX?

Correct AnswerverifiedShow Answer

Examine the IR below and classify the compound.

Correct AnswerverifiedShow Answer

Which of the following statements is (are) accurate about the IR spectrum of compounds I, II, and III below?

Correct AnswerverifiedB

How could spectroscopy be used to distinguish between the following compounds?

Correct AnswerverifiedShow Answer

Consider the three organic compounds drawn below. Which of the following statements is (are) true about the IR spectra of I, II, and III?

Correct AnswerverifiedShow Answer

Which of the following statement(s) is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 69 and shows a prominent peak in its IR spectrum at 2250 cm-1?

Correct AnswerverifiedB

Which of the following statements is (are) true about the IR spectrum of the compound drawn below?

Correct AnswerverifiedShow Answer

Which of the following statements about¹³C NMR isnot true?

Correct Answer
verified

Correct Answer
verified
C

Which of the following statements is (are) true about a compound that has molecular ion peaks in its mass spectrum at mass 170 and 172 and shows prominent peaks in its IR spectrum at 3150-3000 and 1600 cm^-1?

Correct Answer
verified

Which of the following statements is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 104 and shows prominent peaks in its IR spectrum at 3200-2850 cm^-1?

Correct Answer
verified

Which of the following statements is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 94 and shows prominent peaks in its IR spectrum at 3600-3200 and 1600 cm^-1?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
B

Correct Answer
verified

Correct Answer
verified

Which of the following statement(s) is (are) true about a compound that has a molecular ion peak in its mass spectrum at mass 69 and shows a prominent peak in its IR spectrum at 2250 cm^-1?

Correct Answer
verified
B

Correct Answer
verified