Question 1

Which of the following statements best describes the initiation step in the free radical chlorination of methane?

Accepted Answer

It involves the homolytic cleavage of the Cl-Cl bond to generate two chlorine radicals.

Question 2

During the free radical halogenation of butane with $$\mathrm{Br_2$}$$ and light, which hydrogen is most likely to be substituted and why?

Accepted Answer

A secondary hydrogen, because the resulting secondary radical is more stable than a primary radical.

Question 3

What is the major product when cyclohexene is treated with NBS and light ($$hv$$)?

Accepted Answer

3-bromocyclohexene (bromination at the allylic position)

Question 4

Which of the following best explains why tertiary alkyl radicals are more stable than primary alkyl radicals?

Accepted Answer

Tertiary radicals are stabilized by hyperconjugation and alkyl group electron donation.

Question 5

In the radical bromination of toluene ($$\mathrm{C_6H_5CH_3}) $$with $$\mathrm{Br_2$}$$ and $$hv$$, what is the major product?

Accepted Answer

Benzyl bromide ($$\mathrm{C_6H_5CH_2Br})$$

Question 6

Which reagent combination is used for selective bromination at the allylic position of an alkene?

Accepted Answer

NBS and light ($$hv)$$

Question 7

Which of the following polymers is produced by radical polymerization of tetrafluoroethylene?

Accepted Answer

Teflon ($$\mathrm{(C_2F_4)_n})$$

Question 8

Which of the following is a termination step in the free radical chlorination of methane?

Accepted Answer

$$\mathrm{Cl^\cdot + CH_3$^\cdot \rightarrow CH_3Cl}$$

Question 9

A student attempts to brominate cyclohexene with $$\mathrm{Br_2$}$$ and light ($$hv). $$Which position will bromine most likely add?

Accepted Answer

Allylic position (next to the double bond)

Question 10

Which of the following best describes the role of peroxides ($$\mathrm{ROOR}) in $$radical reactions?

Accepted Answer

They act as radical initiators by undergoing homolytic cleavage to generate alkoxy radicals.

Question 11

In the radical bromination of 2-methylpropene with NBS and light, which product is formed?

Accepted Answer

3-bromo-2-methylpropene (bromination at the allylic carbon)

Question 12

Which of the following is NOT a possible termination step in a free radical halogenation reaction?

Accepted Answer

$$\mathrm{CH_4$ + Cl^\cdot \rightarrow CH_3$^\cdot + HCl}$$

Question 13

Which of the following statements about radical polymerization is correct?

Accepted Answer

Radical polymerization involves the growth of polymer chains by successive addition of monomers to a radical site.

Question 14

Which of the following is the correct order of stability for alkyl radicals?

Accepted Answer

Tertiary \u003e Secondary \u003e Primary

Question 15

A chemist wants to selectively brominate the benzylic position of ethylbenzene. Which reagents should be used?

Accepted Answer

$$\mathrm{Br_2$}$$ and light ($$hv)$$

Question 16

Which of the following is a propagation step in the free radical chlorination of methane?

Accepted Answer

$$\mathrm{CH_4$ + Cl^\cdot \rightarrow CH_3$^\cdot + HCl}$$

Question 17

Which of the following best describes the effect of using $$\mathrm{Br_2$}$$ and light ($$hv) on $$cyclohexane?

Accepted Answer

Bromination occurs at the most stable (secondary) carbon radical position.

Question 18

Which of the following is a real-world application of radical polymerization?

Accepted Answer

Production of polyethylene for plastic bottles.

Ch 6, 7, 8

Study Guide - Practice Questions