Organic Chemistry II Quizzes: Test Your Knowledge

Question 1

Which reaction illustrates nucleophilic aromatic substitution?

Accepted Answer

C6H5Cl + NaOCH3 → C6H5OCH3 + NaCl

Answer

CH3CH2Br + NaNH2 → CH3CH2NH2 + NaBr

Answer

(CH3)3CBr + KOH → (CH3)3COH + KBr

Answer

C6H5CH2Br + NaOH → C6H5CH2OH + NaBr

Question 2

Identify the reaction that exemplifies nucleophilic aromatic substitution:

Accepted Answer

Benzene reacts with NH3 to form Aniline

Answer

Benzene reacts with Br2 to form Bromobenzene

Answer

Benzene reacts with CH3Cl to form Toluene

Answer

Phenol reacts with NaOH to form Sodium phenoxide

Question 3

Which of the following reactions is a pericyclic reaction, where reactants transform into products in a single, concerted step?

Accepted Answer

Diels-Alder reaction

Answer

Nucleophilic addition to a carbonyl compound

Answer

Electrophilic aromatic substitution

Answer

SN2 reaction

Question 4

Identify the reaction that proceeds through a radical mechanism:

Accepted Answer

Bromination of alkenes

Answer

Electrophilic aromatic substitution

Answer

Nucleophilic addition to carbonyl compounds

Answer

Diels-Alder reaction

Question 5

Which reaction is an electrophilic aromatic substitution?

Accepted Answer

Nitration of benzene

Answer

Addition of HBr to benzene

Answer

Hydrolysis of ethyl acetate

Answer

Diels-Alder reaction

Question 6

In a nucleophilic aromatic substitution reaction on nitrobenzene, which reagent would act as an effective nucleophile?

Accepted Answer

Sodium methoxide

Answer

Sodium hydroxide

Answer

Potassium permanganate

Answer

Sodium borohydride

Question 7

In electrophilic aromatic substitution, which intermediate is the most reactive?

Accepted Answer

Arenium ion

Answer

Benzene

Answer

Carbanion

Answer

Radical

Question 8

Which of the following reactions is not a type of pericyclic reaction?

Accepted Answer

Nucleophilic addition

Answer

Electrocyclic reactions

Answer

Cycloadditions

Answer

Sigmatropic rearrangements

Question 9

Which of the following reactions is an example of a nucleophilic aromatic substitution reaction, where a nucleophile attacks an electrophile on an aromatic ring?

Accepted Answer

Nitrobenzene + NaOH → Sodium phenoxide

Answer

Benzene + Br2 → Bromobenzene

Answer

Phenol + HCl → Chlorobenzene

Answer

Benzoic acid + SOCl2 → Benzoyl chloride

Question 10

In a nucleophilic aromatic substitution reaction, which type of reactant initiates the attack on the electrophilic aromatic ring?

Accepted Answer

Nucleophile

Answer

Electrophile

Answer

Radical

Answer

Base

Question 11

In the electrophilic aromatic substitution reaction, which substance acts as the electrophile?

Accepted Answer

Acetyl chloride

Answer

Benzene

Answer

Sodium hydroxide

Answer

Water

Question 12

Benzene reacts with nitronium ion (NO2+) via an electrophilic aromatic substitution mechanism. Which of the following options best describes this reaction pathway?

Accepted Answer

Formation of a sigma complex, followed by rearomatization.

Answer

Addition of NO2+ to the benzene ring, followed by proton elimination.

Answer

Formation of a Wheland intermediate, followed by protonation.

Answer

Formation of a carbocation, followed by nucleophilic attack by NO2-.

Question 13

Which of the following reactions does NOT involve a nucleophilic attack on an aromatic ring?

Accepted Answer

Reaction of benzene with sodium amide in liquid ammonia

Answer

Reaction of benzene with chlorine in the presence of iron(III) chloride

Answer

Reaction of benzene with concentrated nitric acid and sulfuric acid

Answer

Reaction of benzene with methylmagnesium bromide in ether

Question 14

In a nucleophilic aromatic substitution reaction, which species acts as the nucleophile?

Accepted Answer

Sodium amide

Answer

Potassium permanganate

Answer

Hydrochloric acid

Answer

Bromine

Question 15

In an electrophilic aromatic substitution reaction, benzene reacts with an electrophile E+. Which product is formed as the major outcome?

Accepted Answer

Ortho- and para-substituted benzene

Answer

Meta-substituted benzene

Answer

1,2-Disubstituted benzene

Answer

Benzene with no substitution

Question 16

In the nucleophilic addition of an alcohol to a ketone, what is the mechanism?

Accepted Answer

Alcohol attacks the carbonyl oxygen, forming a tetrahedral intermediate that collapses to form the product.

Answer

Alcohol directly attacks the carbonyl carbon.

Answer

Ketone attacks the alcohol, forming a tetrahedral intermediate that collapses to form the product.

Answer

Alcohol and ketone form a complex that rearranges to form the product.

Question 17

Which spectroscopic technique provides information about the molecular weight and formula of an organic compound?

Accepted Answer

Mass spectrometry

Answer

Nuclear Magnetic Resonance (NMR) spectroscopy

Answer

Infrared (IR) spectroscopy

Answer

Ultraviolet-Visible (UV-Vis) spectroscopy

Question 18

In organic chemistry, which reagent is most appropriate for oxidizing an aldehyde to produce a carboxylic acid?

Accepted Answer

Potassium permanganate

Answer

Sodium borohydride

Answer

Lithium aluminum hydride

Answer

Grignard reagent

Question 19

In organic chemistry, which reagent is used to transform an aldehyde into an alcohol?

Accepted Answer

Sodium borohydride

Answer

Potassium permanganate

Answer

Hydrochloric acid

Answer

Bromine

Question 20

Which benzene derivative is most reactive towards electrophilic aromatic substitution?

Accepted Answer

Phenol

Answer

4-Methylbenzoic acid

Answer

Nitrobenzene

Answer

Benzonitrile

Question 21

To synthesize a carboxylic acid from an aldehyde, which reagent should an organic chemist use?

Accepted Answer

Potassium permanganate

Answer

Sodium borohydride

Answer

Lithium aluminum hydride

Answer

Grignard reagent

Question 22

Which reaction demonstrates electrophilic aromatic substitution?

Accepted Answer

Benzene reacts with chlorine gas in the presence of iron(III) chloride (FeCl3).

Answer

Benzene reacts with sodium hydroxide (NaOH).

Answer

Benzene reacts with hydrogen gas (H2) in the presence of a nickel catalyst.

Answer

Benzene reacts with potassium permanganate (KMnO4).

Question 23

In the nucleophilic addition of an alcohol to a ketone, what intermediate is formed? Which mechanism is associated with this intermediate?

Accepted Answer

Tetrahedral intermediate; addition-elimination mechanism

Answer

Carbenium ion intermediate; SN1 mechanism

Question 24

In organic chemistry, which electronic transition corresponds to the absorption of ultraviolet light?

Accepted Answer

π → π*

Answer

n → n*

Answer

σ → σ*

Answer

n → π*

Question 25

Which infrared (IR) absorption frequency range (in cm-1) indicates the presence of a carbonyl group (C=O) in an organic molecule?

Accepted Answer

1650-1750 cm-1

Answer

3300-3500 cm-1

Answer

2800-3000 cm-1

Answer

1000-1300 cm-1

Question 26

In a reaction between an acid chloride and an alcohol, what type of product is formed?

Accepted Answer

Ester

Answer

Ketone

Answer

Amide

Answer

Acid

Question 27

In an electrophilic aromatic substitution reaction involving benzene, which reagent is typically employed to yield nitrobenzene?

Accepted Answer

Nitric acid and sulfuric acid

Answer

Acetyl chloride

Answer

Potassium permanganate

Answer

Sodium hydroxide

Question 28

Identify the reaction that results in the formation of a new carbon-carbon bond:

Accepted Answer

Nucleophilic addition to carbonyl compounds

Answer

Electrophilic aromatic substitution

Answer

Pericyclic reactions

Question 29

In a nucleophilic acyl substitution reaction, what intermediate is formed before the final product?

Accepted Answer

Tetrahedral intermediate

Answer

Alkoxide ion

Answer

Carboxylic acid

Answer

Acyl chloride

Question 30

In a Diels-Alder reaction, the dienophile is an electron-deficient compound. Which of the following is the most reactive dienophile?

Accepted Answer

Maleic anhydride (C4H2O3)

Answer

Ethene (C2H4)

Answer

1,3-Butadiene (C4H6)

Answer

Benzene (C6H6)

Question 31

Classify the following organic compounds based on their structure, functionality, and properties:

Accepted Answer

A. Ethane - alkane, B. Ethanol - alcohol, C. Acetic acid - carboxylic acid, D. Benzene - aromatic hydrocarbon

Answer

A. Ethane - alkene, B. Ethanol - ether, C. Acetic acid - ester, D. Benzene - alkyne

Answer

A. Ethane - aldehyde, B. Ethanol - ketone, C. Acetic acid - amide, D. Benzene - phenol

Answer

A. Ethane - amine, B. Ethanol - thiol, C. Acetic acid - anhydride, D. Benzene - pyridine

Question 32

How does organic chemistry contribute to the pharmaceutical industry?

Accepted Answer

Organic chemistry plays a role in designing, synthesizing, and evaluating drug candidates.

Answer

Organic chemistry only designs new drug candidates.

Answer

Organic chemistry only synthesizes drug candidates.

Question 33

Retrosynthesis is a key concept in organic synthesis. How does it guide the planning and execution of organic synthesis in modern drug discovery and development?

Accepted Answer

Retrosynthesis involves working backward from a target molecule to identify simpler starting materials and synthetic steps.

Answer

Retrosynthesis involves using only one-step reactions to construct the target molecule.

Answer

Retrosynthesis is only applicable to the synthesis of small, simple molecules.

Answer

Retrosynthesis does not consider the availability or cost of starting materials.

Question 34

Which principles underpin green chemistry, promoting eco-friendly practices in organic synthesis?

Accepted Answer

Atom economy, waste minimization, renewable feedstock utilization

Answer

Employing hazardous substances, minimizing energy consumption, maximizing product yield

Answer

Using non-polar solvents, maximizing reaction temperature, employing excess reagents

Question 35

In an SN2 reaction, which step governs the overall reaction rate?

Accepted Answer

Formation of the transition state

Answer

Formation of the nucleophile

Answer

Collision between the nucleophile and substrate

Answer

Departure of the leaving group

Question 36

Which of the following species exhibits strong nucleophilic character?

Accepted Answer

Sodium ethoxide

Answer

Water

Answer

Methanol

Answer

Pyridine

Question 37

Which spectroscopic technique utilizes the absorption of electromagnetic radiation by specific functional groups in a sample, allowing for the determination of its molecular structure?

Accepted Answer

Infrared spectroscopy

Answer

Mass spectrometry

Answer

NMR spectroscopy

Answer

UV-Visible spectroscopy

Question 38

In the reaction R-Br + Mg → R-MgBr, what is the type of reaction mechanism involved?

Accepted Answer

Grignard reaction

Answer

Nucleophilic substitution

Answer

Electrophilic addition

Answer

Free radical substitution

Question 39

In the reaction (CH3)2C=CH2 + HBr, what is the major product formed?

Accepted Answer

(CH3)2CHCH2Br

Answer

(CH3)3CBr

Answer

(CH3)CH=CHBr

Answer

(CH3)2CBrCH3

Question 40

Which solvent exhibits the highest polarity?

Accepted Answer

Water

Answer

Hexane

Answer

Dichloromethane

Answer

Ethanol

Question 41

Which of the following is classified as a strong acid?

Accepted Answer

Hydrochloric acid

Answer

Acetic acid

Answer

Phosphoric acid

Answer

Carbonic acid

Question 42

What is the general hybridization of the carbon atom in an alkene?

Accepted Answer

sp2

Answer

sp

Answer

sp3

Answer

sp3d

Question 43

Which of the following is a characteristic functional group of an alcohol?

Accepted Answer

-OH

Answer

-COOH

Answer

-C=O

Answer

-NH2

Question 44

What is the major product of the following reaction: CH3CH2CH2Br + NaOH →?

Accepted Answer

CH3CH2CH2OH

Answer

CH3CH=CH2

Answer

CH3CH2COOH

Answer

CH3CH2CH2NH2

Question 45

Which of the following is the strongest acid?

Accepted Answer

CH3CH2CH2CH2COOH

Answer

CH3COOH

Answer

CH3CH2COOH

Answer

CH3CH2CH2COOH

Question 46

Which of the following is a Lewis acid?

Accepted Answer

H+

Answer

NH3

Answer

OH-

Answer

CH3COOH

Question 47

Which of the following is a resonance structure?

Accepted Answer

A structure that represents the same molecule with different arrangements of electrons

Answer

A structure that represents a different molecule with the same molecular formula

Answer

A structure that represents a transition state

Answer

A structure that represents an intermediate

Question 48

Which spectroscopic technique utilizes the absorption or emission of electromagnetic radiation in the microwave region to provide information about molecular structure?

Accepted Answer

Microwave spectroscopy

Answer

Nuclear Magnetic Resonance (NMR)

Answer

Infrared (IR) spectroscopy

Answer

Ultraviolet-visible (UV-Vis) spectroscopy

Question 49

Which of the following species is considered a strong nucleophile?

Accepted Answer

Hydroxide ion

Answer

Water

Answer

Ammonia

Answer

Methane

Question 50

Which of the following compounds is an example of a heterocyclic compound?

Accepted Answer

Pyridine

Answer

Benzene

Answer

Naphthalene

Answer

Anthracene

Question 51

What is the mechanism of the Diels-Alder reaction?

Accepted Answer

Diene cycloaddition

Answer

Electrophilic addition

Answer

Nucleophilic addition

Answer

Radical addition

Question 52

Which of the following molecules is chiral?

Accepted Answer

(CH3)2CHOH

Answer

CH3CH2OH

Answer

CH3COOH

Answer

CH3CHBrCH3

Question 53

Provide the IUPAC name for the compound CH3CH2CH(CH3)CH2CH3:

Accepted Answer

2-Methylpentane

Answer

3-Methylpentane

Answer

2-Ethylbutane

Answer

3-Ethylpentane

Question 54

Which of the following species is classified as a strong acid?

Accepted Answer

Hydrochloric acid

Answer

Acetic acid

Answer

Carbonic acid

Answer

Water

Question 55

Which of the following statements about IR, NMR, and mass spectrometry is true?

Accepted Answer

IR spectroscopy can identify functional groups.

Accepted Answer

NMR spectroscopy can provide information about the connectivity of atoms in a molecule.

Accepted Answer

Mass spectrometry can determine the molecular weight of a compound.

Answer

All of the above statements are true.

Question 56

Which reagent is most suitable for selectively oxidizing a primary alcohol to an aldehyde?

Accepted Answer

Pyridinium chlorochromate (PCC)

Answer

Sodium borohydride

Answer

Lithium aluminum hydride (LAH)

Answer

Potassium permanganate

Question 57

Which of the following statements accurately describes the electronic structure of aromatic compounds?

Accepted Answer

Aromatic compounds have a planar ring structure with delocalized electrons.

Answer

Aromatic compounds are highly reactive and unstable.

Answer

Aromatic compounds contain alternating double and single bonds.

Answer

Aromatic compounds are only found in natural products.

Question 58

What is the hybridization of the carbon atom in the carbonyl group of an aldehyde?

Accepted Answer

sp2

Answer

sp

Answer

sp3

Answer

sp3d

Question 59

Which of the following compounds exhibits the strongest acidity?

Accepted Answer

Phenol

Answer

Acetic acid

Answer

Ethanol

Answer

Water

Question 60

Which of the following molecules is chiral?

Accepted Answer

2-Butanol

Answer

Methane

Answer

Ethanol

Answer

Carbon dioxide

Question 61

Which of the following compounds is classified as a heterocyclic compound?

Accepted Answer

Pyridine

Answer

Benzene

Answer

Naphthalene

Answer

Anthracene

Question 62

Which of the following functional groups results in a sharp absorption peak in the infrared spectrum around 1715 cm^-1?

Accepted Answer

Carbonyl group

Answer

Alkyl halide group

Answer

Nitrile group

Answer

Ether group

Question 63

Which of the following is the preferred reagent for oxidizing primary alcohols to aldehydes?

Accepted Answer

Pyridinium chlorochromate (PCC)

Answer

Potassium permanganate

Answer

Chromic acid

Answer

Sodium dichromate

Question 64

The reaction of an alkene with a peroxyacid gives:

Accepted Answer

Epoxide

Answer

Alkyl halide

Answer

Diol

Answer

Ketone