Chemistry 9701 · AS & A Level · Halogen compounds

Halogen compounds — practice question

Halogenoalkanes undergo nucleophilic substitution reactions with various reagents.
(a(i))[1]

Give the name of compound A produced when potassium cyanide dissolved in ethanol is added to 1-bromobutane, $\text{CH}_3(\text{CH}_2)_3\text{Br}$, and the mixture is heated under reflux.

(a(ii))[1]

What does the term nucleophile mean?

(a(iii))[1]

Identify the nucleophile in this reaction.

(a(iv))[1]

Explain why this reaction is called a substitution reaction.

(b)[2]

State the reagent(s) and conditions required for $\text{CH}_3(\text{CH}_2)_3\text{Br}$ to react to produce $\text{CH}_3(\text{CH}_2)_3\text{NH}_2$.

(c(i))[2]

Describe and explain the trend in reactivity shown by the different halogenoalkanes in the experiment in which equal amounts of halogenoalkanes are reacted with aqueous silver nitrate and ethanol, using the times for precipitate formation.

(c(ii))[3]

Explain why the SN1 mechanism is preferred for all three halogenoalkanes.

(c(iii))[1]

Identify a halogenoalkane that would usually react with aqueous silver nitrate and ethanol through the SN2 mechanism.

Worked solution & mark scheme

This 12-mark question has a full step-by-step worked solution and mark scheme. One marking point: Pentanenitrile

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI