3.3.1.2 Reaction mechanisms

Which equation represents an initiation step?

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Which statement is correct about the molecule shown?

• It reacts with HBr in an electrophilic substitution reaction.

• It reacts with NaBH₄ in a nucleophilic addition-elimination reaction.

• It reacts with ethanolic KOH in an elimination reaction.

• It reacts with KCN in a nucleophilic substitution reaction.

Which equation is a propagation step in the conversion of trichloromethane into tetrachloromethane by reaction with chlorine in the presence of ultraviolet light?

• CHCl₃ + Cl₂ ⟶ CCl₄ + HCl

• ●CCl₃ + ●Cl ⟶ CCl₄

• CHCl₃ + ●Cl ⟶ CCl₄ + ●H

• ●CCl₃ + Cl₂ ⟶ CCl₄ + ●Cl

The reaction sequence shows how CH₃CH₃ can be converted into BrCH₂CH₂Br

Which step occurs by nucleophilic substitution?

• Step A

• Step B

• Step C

• Step D

In concentrated alkali, propanone reacts with hydroxide ions to form an equilibrium mixture as shown.

Which curly arrow does not appear in the mechanism of this reaction?

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• 
• 

Which of the arrows, labelled A, B, C or D in the mechanism in the diagram, is not correct?

• A

• B

• C

• D

Which of the following is a correct mechanism for the formation of 2-methylbut-2-ene from 2-bromo-3-methylbutane?

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• 

Which one of the following types of reaction mechanism is not involved in the above sequence?

• free-radical substitution

• nucleophilic substitution

• elimination

• nucleophilic addition-elimination

Refer to the following reaction sequence:

Which one of the following types of reaction mechanism is not involved in the above sequence?

• electrophilic addition

• electrophilic substitution

• addition−elimination

• elimination

Which one of the following mechanisms is not involved in the reaction sequence below?

CH₃CH₃ → CH₃CH₂Cl → CH₃CH₂OH → CH₂=CH₂ → CH₃CH₂Br

• electrophilic addition

• electrophilic substitution

• nucleophilic substitution

• free-radical substitution