Which of the following statements is false?
A)
Furan, pyrrole, and thiophene are more reactive than benzene in electrophilic aromatic substitution.
B)
Electrophilic substitution in pyridine occurs mainly in the 2- and 4-positions.
C)
Electrophilic substitution in furan, pyrrole, and thiophene occurs mainly in the 2-position.
D)
Pyridine is more basic than pyrrole.
E)
An unshared electron pair on O, N, or S is part of the aromatic p system in furan, pyrrole, and thiophene.
Question 2Which of the following heterocyclic compounds is
not aromatic?
A)
D)
B)
E)
C)
Question 3Which of the following molecules can be classified as a heterocycle?
A)
D)
B)
E)
C)
Question 4The structural formula for furan is:
A)
D)
B)
E)
C)
Question 5The name of
is:
A)
pyrrole
B)
furan
C)
pyridine
D)
pyrimidine
E)
thiophene
Question 6What type of heterocycle is present in both histamine and histidine?
A)
indole
B)
pyrimidine
C)
purine
D)
imidazole
E)
thiazole
Question 7What type of heterocycle is found in guanine?
A)
purine
B)
pyrimidine
C)
pyridine
D)
quinoline
E)
oxazole
Question 8To what family of heterocyclic compounds do both serotonin and tryptophan belong?
A)
imidazole
B)
oxazole
C)
thiazole
D)
indole
E)
pyridazine
Question 9The name of the heterocycle below is:
A)
pyrrole
B)
furan
C)
thiophene
D)
pyryllium
E)
phenol
Question 10The name of the heterocycle below is:
A)
pyrrole
B)
furan
C)
thiophene
D)
pyryllium
E)
phenol
Question 11The heterocycle cytosine, found in nucleic acids, is an example of a:
A)
purine
B)
pyrimidine
C)
pyridine
D)
piperidine
E)
pyrazine
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Early in the twentieth century, when malnutrition was common, companies such as this one advertised
Acid-Reactive Salts
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The human X chromosome (left) and the Y chromosome (right). This false-color scanning electron micro