Question 1

Which of the following will produce (M+2)+ • peak one third the intensity of M+• peak?

Accepted Answer

A)  nitrogen 
B)  chlorine 
C)  bromine 
D)  oxygen 
E)  B and C 
A)  nitrogen 
B)  chlorine 
C)  bromine 
D)  oxygen 
E)  B and C B

Question 2

Warmer objects emit more __________ radiation.

Accepted Answer

IR

Question 3

Which of the following is expected to be the base peak in the mass spectrum of CH3CH2NH2?

Accepted Answer

A)  15 
B)  28 
C)  30 
D)  45 
E)  none of these 
A)  15 
B)  28 
C)  30 
D)  45 
E)  none of these C

Question 4

Which of the following bonds has the weakest absorption?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  I and IV 
E)  I and III 
A)  I 
B)  II 
C)  III 
D)  I and IV 
E)  I and III

Question 5

Which of the following is true about the (M+1)+• peak on the mass spectrum of a hydrocarbon?

Accepted Answer

A)  it is always the most abundant peak 
B)  it is due to the 13C isotope of carbon 
C)  it has a m/z value lower than the molecular ion 
D)  it is useful in calculating number of carbon atoms 
E)  B and D 
A)  it is always the most abundant peak 
B)  it is due to the 13C isotope of carbon 
C)  it has a m/z value lower than the molecular ion 
D)  it is useful in calculating number of carbon atoms 
E)  B and D

Question 6

A stationary phase separates the components of a mixture based on their _____________ and __________ .

Accepted Answer

A)  boiling points, their affinity for the stationary phase 
B)  melting points, their repulsion for the stationary phase 
C)  molecular weights, melting points 
D)  solubility in water, in methanol 
E)  heat of vaporization, heat of sublimation 
A)  boiling points, their affinity for the stationary phase 
B)  melting points, their repulsion for the stationary phase 
C)  molecular weights, melting points 
D)  solubility in water, in methanol 
E)  heat of vaporization, heat of sublimation

Question 7

Which molecular formula is consistent with the following mass spectral data? M+• at m/z = 84, relative height = 10.0%
(M+1)+• at m/ z = 85, relative height = 0.56%

Accepted Answer

A)  C5H10O 
B)  C5H8O 
C)  C5H24 
D)  C6H12 
E)  C4H6O2 
A)  C5H10O 
B)  C5H8O 
C)  C5H24 
D)  C6H12 
E)  C4H6O2

Question 8

Which of the following are units for wavenumber in IR spectroscopy?

Accepted Answer

A)  cm-1 
B)  cm 
C)  J·s-1 
D)  mm 
E)  J·s 
A)  cm-1 
B)  cm 
C)  J·s-1 
D)  mm 
E)  J·s

Question 9

Which of the following is expected to be the base peak in the mass spectrum of CH3(CH2)4OH?

Accepted Answer

A)  88 
B)  55 
C)  42 
D)  31 
E)  none of these 
A)  88 
B)  55 
C)  42 
D)  31 
E)  none of these

Question 10

Which of the following compounds will show absorptions at 1640 cm-1, 2950 cm-1 and 3050 cm-1 on the IR spectrum?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 11

For the following reaction, which of the following change(s) in the IR spectrum is consistent with conversion of the reactant to the product?

Accepted Answer

A)  absorption at 2150 cm-1 should disappear 
B)  absorption at 3300 cm-1 and 2150 cm-1 should disappear 
C)  absorption at 2250 cm-1 should disappear, a new absorption at 3300 cm-1 should appear 
D)  absorption at 1650 cm-1 should disappear, a new absorption at 3300 cm-1 should appear 
E)  absorption at 3300 cm-1 and 2150 cm-1 should disappear, a new absorption at 1720 cm-1 should appear 
A)  absorption at 2150 cm-1 should disappear 
B)  absorption at 3300 cm-1 and 2150 cm-1 should disappear 
C)  absorption at 2250 cm-1 should disappear, a new absorption at 3300 cm-1 should appear 
D)  absorption at 1650 cm-1 should disappear, a new absorption at 3300 cm-1 should appear 
E)  absorption at 3300 cm-1 and 2150 cm-1 should disappear, a new absorption at 1720 cm-1 should appear

Question 12

A compound with molecular formula C4H8O2, shows absorptions at 2500-3300 cm-1 (broad), 1720 cm-1 and at 1200 cm-1 on the IR spectrum. Propose a possible structure for this compound.

Accepted Answer

Question 13

Concentrated alcohols show a _____absorption in the region of 3200-3600 cm-1, due to _____.

Accepted Answer

A)  sharp, hydrogen bonding 
B)  broad, hydrogen bonding 
C)  sharp, polarity 
D)  broad, polarity 
A)  sharp, hydrogen bonding 
B)  broad, hydrogen bonding 
C)  sharp, polarity 
D)  broad, polarity

Question 14

Propose a possible structure for a compound with molecular formula C7H12O2 that shows absorption at 1720 cm-1 and no absorption in the range of 1500 - 1700 cm-1 or 2600 - 2800 cm-1 in its IR spectrum.

Accepted Answer

Question 15

Which of the following is expected to be the base peak in the mass spectrum of 2-methyl-2-butanol?

Accepted Answer

A)  73 
B)  55 
C)  43 
D)  31 
E)  59 
A)  73 
B)  55 
C)  43 
D)  31 
E)  59

Question 16

Which of the m/z values correspond to the molecular ion peak in the following mass spectrum?

Accepted Answer

A)  45 
B)  44 
C)  29 
D)  15 
E)  30 
A)  45 
B)  44 
C)  29 
D)  15 
E)  30

Question 17

Provide the structures of the fragments that result when the molecular ion of 2-heptanone undergoes fragmentation via McLafferty rearrangement.

Accepted Answer

The answer of Provide the structures of the fragments that...

Question 18

Which of the following m/z values corresponds to the base peak for 2-chloro-2-methylpropane?

Accepted Answer

A)  15 
B)  92 
C)  77 
D)  47 
E)  57 
A)  15 
B)  92 
C)  77 
D)  47 
E)  57

Question 19

Arrange the following electromagnetic radiation in decreasing (highest to lowest) order of frequency.

Accepted Answer

A)  V > III > IV > II > I 
B)  II > V > III > IV > I 
C)  I > IV > III > V > II 
D)  V > II > IV > III > I 
E)  II > IV > V > III > I 
A)  V > III > IV > II > I 
B)  II > V > III > IV > I 
C)  I > IV > III > V > II 
D)  V > II > IV > III > I 
E)  II > IV > V > III > I

Question 20

Which of the following bonds has the weakest absorption?

Accepted Answer

A)  C=C 
B)  O-H 
C)  C=O 
D)  sp3 C-H 
E)  A and D 
A)  C=C 
B)  O-H 
C)  C=O 
D)  sp3 C-H 
E)  A and D

Exam 14: Infrared Spectroscopy and Mass Spectrometry

Which of the following will produce (M+2)+ • peak one third the intensity of M+• peak?

Warmer objects emit more __________ radiation.

Which of the following is expected to be the base peak in the mass spectrum of CH3CH2NH2?

Which of the following bonds has the weakest absorption?

Which of the following is true about the (M+1)+• peak on the mass spectrum of a hydrocarbon?

A stationary phase separates the components of a mixture based on their _____________ and __________ .

Which molecular formula is consistent with the following mass spectral data? M+• at m/z = 84, relative height = 10.0% (M+1)+• at m/ z = 85, relative height = 0.56%

Which of the following are units for wavenumber in IR spectroscopy?

Which of the following is expected to be the base peak in the mass spectrum of CH3(CH2)4OH?

Which of the following compounds will show absorptions at 1640 cm-1, 2950 cm-1 and 3050 cm-1 on the IR spectrum?

For the following reaction, which of the following change(s) in the IR spectrum is consistent with conversion of the reactant to the product?

A compound with molecular formula C4H8O2, shows absorptions at 2500-3300 cm-1 (broad), 1720 cm-1 and at 1200 cm-1 on the IR spectrum. Propose a possible structure for this compound.

Concentrated alcohols show a _____absorption in the region of 3200-3600 cm-1, due to _____.

Propose a possible structure for a compound with molecular formula C7H12O2 that shows absorption at 1720 cm-1 and no absorption in the range of 1500 - 1700 cm-1 or 2600 - 2800 cm-1 in its IR spectrum.

Which of the following is expected to be the base peak in the mass spectrum of 2-methyl-2-butanol?

Which of the m/z values correspond to the molecular ion peak in the following mass spectrum?

Provide the structures of the fragments that result when the molecular ion of 2-heptanone undergoes fragmentation via McLafferty rearrangement.

Which of the following m/z values corresponds to the base peak for 2-chloro-2-methylpropane?

Arrange the following electromagnetic radiation in decreasing (highest to lowest) order of frequency.

Which of the following bonds has the weakest absorption?

A Review of General Chemistry: Electrons, Bonds, and Molecular Properties

Molecular Representations

Acids and Bases

Alkanes and Cycloalkanes

Stereoisomerism

Chemical Reactivity and Mechanisms

Alkyl Halides: Nucleophilic Substitution and Elimination Reactions

Addition Reactions of Alkenes

Alkynes

Radical Reactions

Synthesis

Alcohols and Phenols

Ethers and Epoxides; Thiols and Sulfides

Nuclear Magnetic Resonance Spectroscopy

Conjugated Pi Systems and Pericyclic Reactions

Aromatic Compounds

Aromatic Substitution Reactions

Aldehydes and Ketones

Carboxylic Acids and Their Derivatives

Alpha Carbon Chemistry: Enols and Enolates

Amines

Introduction to Organometallic Compounds

Carbohydrates

Amino Acids, Peptides, and Proteins

Lipids

Synthetic Polymers

Filters

Which of the following will produce (M+2)⁺ • peak one third the intensity of M⁺• peak?

Which of the following is expected to be the base peak in the mass spectrum of CH₃CH₂NH₂?

Which of the following is true about the (M+1)⁺• peak on the mass spectrum of a hydrocarbon?

A stationary phase separates the components of a mixture based on their ___ and .

Which molecular formula is consistent with the following mass spectral data? M⁺•at m/z = 84, relative height = 10.0% (M+1)⁺• at m/ z = 85, relative height = 0.56%

Which of the following is expected to be the base peak in the mass spectrum of CH₃(CH₂)₄OH?

Which of the following compounds will show absorptions at 1640 cm^-1, 2950 cm^-1and 3050 cm^-1 on the IR spectrum?

A compound with molecular formula C₄H₈O₂, shows absorptions at 2500-3300 cm^-1 (broad), 1720 cm^-1 and at 1200 cm^-1 on the IR spectrum. Propose a possible structure for this compound.

Concentrated alcohols show a _absorption in the region of 3200-3600 cm^-1, due to _.

Propose a possible structure for a compound with molecular formula C₇H₁₂O₂ that shows absorption at 1720 cm^-1 and no absorption in the range of 1500 - 1700 cm^-1 or 2600 - 2800 cm^-1 in its IR spectrum.