WGU Chemistry D425 Verified Multiple Choice and
Conceptual Actual Emended Exam Questions With
Reviewed 100% Correct Detailed Answers
Guaranteed Pass!!Current Update
1. Calculate the minimum resolving power m/Δm for a mass spectrometer to
successfully separate m/z 125.135 from 125.293.
a. 729
b. 792
c. 972
d. 927 - ANSWER b. 792
2. Which of the following statements with regard to the demonstrated
ionization mechanism of electron ionization below is FALSE?
a. the resultant mass spectrum will show the m/z of A
b. the resultant mass spectrum will show the m/z of AB
c. the resultant mass spectrum will show the m/z of B
d. the resultant mass spectrum will show the m/z of BC - ANSWER
c. the resultant mass spectrum will show the m/z of B
3. The following mass spectrum strongly indicates that the molecular ion
contains one:
a. bromine atom
b. chlorine atom
c. silicon atom
d. sulfur atom - ANSWER a. bromine atom
,4. The following mass spectrum strongly indicates that the molecular ion
contains one:
a. bromine atom
b. chlorine atom
c. silicon atom
d. sulfur atom - ANSWER b. chlorine atom
5. The number of carbons in the molecular ion can be estimated with the
intensity of the isotope (A+1) signal. In addition, the presence many ___
atoms in the molecule should be considered due to their accumulated
contribution to the isotope (A+1) signal.
a. H
b. F
c. N
d. O - ANSWER c. N
6. In the chemical ionization mass spectrum of a compound, the peak with the
most significant intensity at the high end of the mass spectrum at m/z 227
is suspected to be MH+. If this is so, the number of nitrogen atoms in the
compound can be:
a. an odd number
b. an even number
c. zero
d. A and C
e. B and C - ANSWER e. B and C
7. Analytes must be ionized prior to entering the mass analyzer in a mass
spectrometer. Electron ionization and chemical ionization are two ionization
techniques. Which of the following statements is FALSE regarding either
technique?
, a. electron ionization uses an electron beam to create molecular ions,
M+
b. electron ionization gives very little fragmentation
c. the ionized reagent gas in chemical ionization undergoes a complex
set of chemical reactions
d. chemical ionization creates MH+ - ANSWER b. electron ionization
gives very little fragmentation
8. A sample containing only carbon and hydrogen was analyzed. The molecular
ion was identified to be located at m/z = 142. The normalized abundance of
the m/z = 143 versus m/z = 142 was 12.3%. Please estimate the number of
carbons present in the molecule.
a. 9
b. 10
c. 11
d. 12 - ANSWER c. 11
9. During LC operations, air trapped in the column can result in very broad and
obviously _________ chromatographic peaks.
a. fronting
b. tailing - ANSWER a. fronting
10.Which of the following statements is FALSE about the microporous particles
of silica used by LC?
a. the particles have large surface area
b. greater than 99% of the particle surface area is inside the pores
c. pores must be wide enough for the solvent and analytes to enter
freely
Conceptual Actual Emended Exam Questions With
Reviewed 100% Correct Detailed Answers
Guaranteed Pass!!Current Update
1. Calculate the minimum resolving power m/Δm for a mass spectrometer to
successfully separate m/z 125.135 from 125.293.
a. 729
b. 792
c. 972
d. 927 - ANSWER b. 792
2. Which of the following statements with regard to the demonstrated
ionization mechanism of electron ionization below is FALSE?
a. the resultant mass spectrum will show the m/z of A
b. the resultant mass spectrum will show the m/z of AB
c. the resultant mass spectrum will show the m/z of B
d. the resultant mass spectrum will show the m/z of BC - ANSWER
c. the resultant mass spectrum will show the m/z of B
3. The following mass spectrum strongly indicates that the molecular ion
contains one:
a. bromine atom
b. chlorine atom
c. silicon atom
d. sulfur atom - ANSWER a. bromine atom
,4. The following mass spectrum strongly indicates that the molecular ion
contains one:
a. bromine atom
b. chlorine atom
c. silicon atom
d. sulfur atom - ANSWER b. chlorine atom
5. The number of carbons in the molecular ion can be estimated with the
intensity of the isotope (A+1) signal. In addition, the presence many ___
atoms in the molecule should be considered due to their accumulated
contribution to the isotope (A+1) signal.
a. H
b. F
c. N
d. O - ANSWER c. N
6. In the chemical ionization mass spectrum of a compound, the peak with the
most significant intensity at the high end of the mass spectrum at m/z 227
is suspected to be MH+. If this is so, the number of nitrogen atoms in the
compound can be:
a. an odd number
b. an even number
c. zero
d. A and C
e. B and C - ANSWER e. B and C
7. Analytes must be ionized prior to entering the mass analyzer in a mass
spectrometer. Electron ionization and chemical ionization are two ionization
techniques. Which of the following statements is FALSE regarding either
technique?
, a. electron ionization uses an electron beam to create molecular ions,
M+
b. electron ionization gives very little fragmentation
c. the ionized reagent gas in chemical ionization undergoes a complex
set of chemical reactions
d. chemical ionization creates MH+ - ANSWER b. electron ionization
gives very little fragmentation
8. A sample containing only carbon and hydrogen was analyzed. The molecular
ion was identified to be located at m/z = 142. The normalized abundance of
the m/z = 143 versus m/z = 142 was 12.3%. Please estimate the number of
carbons present in the molecule.
a. 9
b. 10
c. 11
d. 12 - ANSWER c. 11
9. During LC operations, air trapped in the column can result in very broad and
obviously _________ chromatographic peaks.
a. fronting
b. tailing - ANSWER a. fronting
10.Which of the following statements is FALSE about the microporous particles
of silica used by LC?
a. the particles have large surface area
b. greater than 99% of the particle surface area is inside the pores
c. pores must be wide enough for the solvent and analytes to enter
freely
