Question 1

Which of the following best describes a primary alkyl halide?

Accepted Answer

A halogen attached to a carbon bonded to only one other carbon.

Question 2

Why is the C–X bond in alkyl halides polar?

Accepted Answer

Because halogens are more electronegative than carbon, creating a dipole.

Question 3

Which of the following alkyl halides is most reactive in nucleophilic substitution reactions?

Accepted Answer

Primary alkyl halide

Question 4

Which solvent is commonly used as an aprotic, non-acidic solvent in organic reactions?

Accepted Answer

Dichloromethane ($CH_2Cl_2$)

Question 5

In the free radical bromination of alkanes, which carbon does bromine preferentially add to?

Accepted Answer

The most substituted carbon

Question 6

What is the major product when cyclopentane is subjected to bromination with $Br_2$ and light?

Accepted Answer

Bromine adds to the most substituted carbon.

Question 7

Which of the following best explains why bromination is more selective than chlorination in free radical halogenation?

Accepted Answer

Bromine radicals are less reactive and more selective than chlorine radicals.

Question 8

Which of the following is a common use of alkyl halides in organic synthesis?

Accepted Answer

As electrophiles in substitution and elimination reactions

Question 9

What is the role of NBS (N-bromosuccinimide) in the bromination of alkenes?

Accepted Answer

It provides a controlled source of bromine for allylic bromination.

Question 10

Which position does bromine add to in the benzylic bromination of toluene using NBS and light?

Accepted Answer

To the methyl group adjacent to the benzene ring (benzylic position)

Question 11

Which of the following reactions is an example of an elimination reaction involving an alkyl halide?

Accepted Answer

Alkyl halide reacts with a base to form an alkene and a halide ion.

Question 12

Which of the following best describes the mechanism of free radical bromination?

Accepted Answer

Initiation, propagation, and termination steps involving radicals.

Question 13

A student wants to synthesize 1-bromopentane from pentane. Which reagent and condition should they use?

Accepted Answer

$Br_2$ and light

Question 14

Which of the following statements about alkyl halides is FALSE?

Accepted Answer

Alkyl halides are always nonpolar molecules.

Question 15

In the E2 elimination of an alkyl halide, which of the following is required?

Accepted Answer

A strong base and an anti-periplanar arrangement of the leaving group and hydrogen.

Question 16

Which of the following alkyl halides would be most reactive in an SN1 reaction?

Accepted Answer

Tertiary alkyl halide

Question 17

What is the major product when 2-methylpentane is brominated with $Br_2$ and light?

Accepted Answer

Bromine adds to the tertiary carbon.

Question 18

Which of the following best explains the use of alkyl halides as solvents?

Accepted Answer

They are aprotic and non-acidic, making them suitable for many organic reactions.

Question 19

During the bromination of cyclopentane, which product is formed in greatest amount?

Accepted Answer

Bromocyclopentane with Br on the most substituted carbon.

Alkyl Halides: Structure, Uses, and Synthesis

Study Guide - Practice Questions