$$\text{rate} = k[\text{R-X}][\text{Nuc}]$$

Question 1

Which of the following best describes an alkyl halide?

Accepted Answer

A halogen atom bonded to an sp\^3 hybridized carbon of an alkyl group.

Question 2

Which compound is a geminal dihalide?

Accepted Answer

CH\_2Br\_2

Question 3

Why are alkyl halides highly reactive in nucleophilic substitution reactions?

Accepted Answer

Because the carbon-halogen bond is highly polarized, making the carbon electrophilic.

Question 4

Which of the following solvents would most enhance the nucleophilicity of an anion in an S\_N2 reaction?

Accepted Answer

Dimethylformamide (DMF)

Question 5

Which statement correctly compares the rates of S\_N2 reactions for methyl, primary, secondary, and tertiary alkyl halides?

Accepted Answer

Methyl \u003e Primary \u003e Secondary \u003e Tertiary

Question 6

Which of the following is a good leaving group in nucleophilic substitution reactions?

Accepted Answer

Iodide ion (I\^-)

Question 7

A student attempts to react tert-butyl bromide with sodium methoxide in methanol. Which mechanism is most likely to occur?

Accepted Answer

E2

Question 8

Which of the following best explains why S\_N2 reactions are stereospecific?

Accepted Answer

They involve a concerted backside attack, resulting in inversion of configuration.

Question 9

Which of the following factors increases the rate of an S\_N1 reaction?

Accepted Answer

Using a more stable carbocation intermediate.

Question 10

Which of the following is the rate law for an S\_N2 reaction?

Accepted Answer

$$	ext{rate} = k[	ext{R-X}][	ext{Nuc}]$$

Question 11

Which of the following statements about E2 elimination is correct?

Accepted Answer

It requires the hydrogen and leaving group to be anti-coplanar.

Question 12

According to Zaitsev's rule, which alkene is favored in an elimination reaction?

Accepted Answer

The most substituted alkene.

Question 13

Which of the following is a common rearrangement observed in S\_N1 and E1 reactions?

Accepted Answer

Hydride shift

Question 14

Which of the following nucleophiles is expected to be the strongest in a polar aprotic solvent?

Accepted Answer

F\^-

Question 15

Which of the following statements is true regarding the stereochemistry of S\_N1 reactions?

Accepted Answer

They result in racemization due to attack on both faces of the carbocation.

Question 16

Which of the following is NOT a factor that makes a good leaving group?

Accepted Answer

Being a strong base.

Question 17

A chemist wants to convert cyclohexene to 3-bromocyclohexene using allylic bromination. Which reagent should be used?

Accepted Answer

N-bromosuccinimide (NBS) with light

Question 18

Which of the following statements best explains why tertiary alkyl halides do not undergo S\_N2 reactions?

Accepted Answer

Steric hindrance prevents the nucleophile from attacking the electrophilic carbon.

Question 19

Which of the following is the major product when 2-bromo-2-methylbutane is treated with methanol?

Accepted Answer

2-methoxy-2-methylbutane

Question 20

Which of the following statements correctly compares the requirements for E1 and E2 reactions?

Accepted Answer

E2 requires a strong base, while E1 does not.

Nucleophilic Substitution and Elimination: Alkyl Halides, Mechanisms, and Reactivity

Study Guide - Practice Questions