Question 1

Which of the following statements best describes constitutional isomers?

Accepted Answer

They have the same molecular formula but different connectivity of atoms.

Question 2

Which of the following molecules contains a functional group that is classified as an ether?

Accepted Answer

$$\mathrm{CH_3CH_2OCH_3}$$

Question 3

A molecule with the formula $$\mathrm{C_4H_{10}}$$ can exist as two different compounds. What type of isomerism is this an example of?

Accepted Answer

Constitutional isomerism

Question 4

Which of the following best explains why trans-2-butene has a higher melting point than cis-2-butene?

Accepted Answer

Trans isomers pack more efficiently in the solid state, leading to stronger intermolecular forces.

Question 5

Which of the following is the correct IUPAC name for the compound shown below?

$$\mathrm{CH_3CH_2CH(CH_3$)CH_2CH_3}$$

Accepted Answer

3-Methylpentane

Question 6

Which of the following statements about the stability of cyclohexane conformations is correct?

Accepted Answer

The chair conformation is more stable than the boat conformation due to minimized torsional strain.

Question 7

Which of the following functional groups is present in both aldehydes and ketones?

Accepted Answer

Carbonyl group ($$\mathrm{C=O})$$

Question 8

Which of the following compounds will have the highest boiling point?

A. $$\mathrm{CH_3CH_2CH_2OH}
B$$. $$\mathrm{CH_3CH_2OCH_3}
C$$. $$\mathrm{CH_3CH_2CH_3}
D$$. $$\mathrm{CH_3COCH_3}$$

Accepted Answer

$$\mathrm{CH_3CH_2CH_2OH}$$

Question 9

Which of the following best describes the hybridization of the central carbon atom in ethene ($$\mathrm{C_2H_4}$$)?

Accepted Answer

$$sp^2$$

Question 10

Which of the following statements about resonance structures is correct?

Accepted Answer

Resonance structures differ only in the placement of electrons, not atoms.

Question 11

Which of the following is the most stable carbocation?

Accepted Answer

Tertiary ($$3^\circ) $$carbocation

Question 12

Which of the following best explains why alcohols generally have higher boiling points than alkanes of similar molecular weight?

Accepted Answer

Alcohols can form hydrogen bonds, which require more energy to break.

Question 13

Which of the following is a correct statement about the acidity of carboxylic acids compared to alcohols?

Accepted Answer

Carboxylic acids are more acidic because their conjugate base is stabilized by resonance.

Question 14

Which of the following best describes the difference between a ketone and an aldehyde?

Accepted Answer

A ketone has the carbonyl group bonded to two carbon atoms, while an aldehyde has it bonded to at least one hydrogen.

Question 15

Which of the following is the correct order of increasing boiling points for the following compounds?

$$\mathrm{CH_4$}$$, $$\mathrm{CH_3Cl}$$, $$\mathrm{CH_3OH}$$

Accepted Answer

$$\mathrm{CH_4$} \u003c \mathrm{CH_3Cl} \u003c \mathrm{CH_3OH}$$

Question 16

Which of the following best describes the effect of branching on the boiling point of alkanes?

Accepted Answer

Branching decreases the boiling point due to decreased surface area.

Question 17

Which of the following is the correct product of the complete combustion of ethanol ($$\mathrm{C_2H_5OH}$$)?

Accepted Answer

$$\mathrm{2CO_2 + 3H_2O}$$

Question 18

Which of the following statements about the nucleophilicity of halide ions in protic solvents is correct?

Accepted Answer

Iodide ($$\mathrm{I^-}) is $$the most nucleophilic due to its large size and weak solvation.

Question 19

Which of the following best explains why the carbonyl carbon in aldehydes and ketones is electrophilic?

Accepted Answer

The oxygen atom is more electronegative, pulling electron density away from the carbon.

Organic Chemistry Fundamentals: Structure, Isomerism, Functional Groups, and Alkanes

Study Guide - Practice Questions