CHEM 219 ORGANIC CHEMISTRY MODULE
5 PRACTICE EXAMINATION 2026
QUESTIONS WITH ANSWERS GRADED A+
◍ Williamson Synthesis.
Answer: Two steps to produce an asymmetric ether, in fist step alcohol is
converted to its conjugate base, (Alkoxide ion RO-) by reacting the alcohol
with sodium or potassium metal. The Alkoxide is then reacted as a
nucleophile in an Sn2 displacement, typically on an alkyl halide substrate.
Net result is an ether where R does not equal R. Typically primary or
secondary only.
◍ A. Protic, Sn1
B. Aprotic, Sn2
C. Aprotic, Sn2D, Protic, Sn1.
Answer: Classify the following solvents as protic or aprotic. Would this
solvent enhance the rate of an Sn1 or Sn2 reaction?
◍ PCC Oxidation of Alcohols.
Answer: Pyridinium Chlorochromate - oxidizes primary alcohols to the
aldehyde stage and stop there without further oxidation to the Carboxylic
acid. -Dichloromethane (CH2Cl2) is typically the solvent used for PCC
oxidation o alcohols
◍ Sodium Borohydride (NaBH4).
Answer: Advantages - reduces all aldehydes and ketones. Stable and can be
used in mixed aqueous systems. Very efficient as one Borohydride can
transfer all 4 of its H atoms as hydride ions and reduce 4 carbonyls
◍ Crown Ethers.
Answer: Can solvate cations within theur interior cavity, size of the ring
, controls which cations can fit into the cavity, this allows ionic compounds to
be dissolved in relatively non-polar organic solvents
◍ Peroxyacid.
Answer: Analogous in structure to a Carboxylic acid but contains an extra
oxygen between the carbonyl and hydroxy group
◍ ZAitsev's Rule.
Answer: The production of the more highly substituted alkene as the major
product.
◍ Ester.
Answer: For the following reaction. predict what functional group the
product of the reaction would contain. Note that you are not being asked to
generate the IUPAC name of the product, simply to state what functional
group it would contain.
◍ Aldehydes are reduced to....
Answer: Primary alcohols
◍ IUPAC aldehyde nomenclature.
Answer: -al (suffix)Parent chain is named based in the number of C in the
longest chain containing H-C=O(formal group)
◍ D.The substrate proceeds with an SN2 mechanism, therefore the rate relies
on the concentration of both the nucleophile and substrate. If the
concentrations of each are increased by 2 the rate would increase by 4.
Answer: Consider the substitution reaction of 1-bromobutane with
hydroxide ionAssuming no other changes, what effect on the rate would
result from simultaneously doubling the concentrations of both butyl
bromide and hydroxide ion? ExplainA)No effectB) It would double the
rateC) It would triple the rateD) It would increase the rate four timesE) It
would increase the rate six times
◍ True.
Answer: Determine if the following statement regarding substitution and
elimination mechanisms are true or falseSn1 mechanisms are unimolecular,
5 PRACTICE EXAMINATION 2026
QUESTIONS WITH ANSWERS GRADED A+
◍ Williamson Synthesis.
Answer: Two steps to produce an asymmetric ether, in fist step alcohol is
converted to its conjugate base, (Alkoxide ion RO-) by reacting the alcohol
with sodium or potassium metal. The Alkoxide is then reacted as a
nucleophile in an Sn2 displacement, typically on an alkyl halide substrate.
Net result is an ether where R does not equal R. Typically primary or
secondary only.
◍ A. Protic, Sn1
B. Aprotic, Sn2
C. Aprotic, Sn2D, Protic, Sn1.
Answer: Classify the following solvents as protic or aprotic. Would this
solvent enhance the rate of an Sn1 or Sn2 reaction?
◍ PCC Oxidation of Alcohols.
Answer: Pyridinium Chlorochromate - oxidizes primary alcohols to the
aldehyde stage and stop there without further oxidation to the Carboxylic
acid. -Dichloromethane (CH2Cl2) is typically the solvent used for PCC
oxidation o alcohols
◍ Sodium Borohydride (NaBH4).
Answer: Advantages - reduces all aldehydes and ketones. Stable and can be
used in mixed aqueous systems. Very efficient as one Borohydride can
transfer all 4 of its H atoms as hydride ions and reduce 4 carbonyls
◍ Crown Ethers.
Answer: Can solvate cations within theur interior cavity, size of the ring
, controls which cations can fit into the cavity, this allows ionic compounds to
be dissolved in relatively non-polar organic solvents
◍ Peroxyacid.
Answer: Analogous in structure to a Carboxylic acid but contains an extra
oxygen between the carbonyl and hydroxy group
◍ ZAitsev's Rule.
Answer: The production of the more highly substituted alkene as the major
product.
◍ Ester.
Answer: For the following reaction. predict what functional group the
product of the reaction would contain. Note that you are not being asked to
generate the IUPAC name of the product, simply to state what functional
group it would contain.
◍ Aldehydes are reduced to....
Answer: Primary alcohols
◍ IUPAC aldehyde nomenclature.
Answer: -al (suffix)Parent chain is named based in the number of C in the
longest chain containing H-C=O(formal group)
◍ D.The substrate proceeds with an SN2 mechanism, therefore the rate relies
on the concentration of both the nucleophile and substrate. If the
concentrations of each are increased by 2 the rate would increase by 4.
Answer: Consider the substitution reaction of 1-bromobutane with
hydroxide ionAssuming no other changes, what effect on the rate would
result from simultaneously doubling the concentrations of both butyl
bromide and hydroxide ion? ExplainA)No effectB) It would double the
rateC) It would triple the rateD) It would increase the rate four timesE) It
would increase the rate six times
◍ True.
Answer: Determine if the following statement regarding substitution and
elimination mechanisms are true or falseSn1 mechanisms are unimolecular,
