The reaction sequence shows how CH₃CH₃ can be converted into BrCH₂CH₂Br
CH₃CH₃ + Cl₂ → Step A → CH₃CH₂Cl
NaOH → Step B → CH₃CH₂OH
Step C → H₂SO₄ → CH₂=CH₂
BrCH₂CH₂Br + Br₂ → Step D → CH₂=CH₂
Which step occurs by nucleophilic substitution? - AQA - A-Level Chemistry - Question 14 - 2017 - Paper 3
Question 14
The reaction sequence shows how CH₃CH₃ can be converted into BrCH₂CH₂Br
CH₃CH₃ + Cl₂ → Step A → CH₃CH₂Cl
NaOH → Step B → CH₃CH₂OH
Step C → H₂S... show full transcript
Worked Solution & Example Answer:The reaction sequence shows how CH₃CH₃ can be converted into BrCH₂CH₂Br
CH₃CH₃ + Cl₂ → Step A → CH₃CH₂Cl
NaOH → Step B → CH₃CH₂OH
Step C → H₂SO₄ → CH₂=CH₂
BrCH₂CH₂Br + Br₂ → Step D → CH₂=CH₂
Which step occurs by nucleophilic substitution? - AQA - A-Level Chemistry - Question 14 - 2017 - Paper 3
Step 1
Step A
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Answer
In Step A, the conversion involves the reaction of ethane (CH₃CH₃) with chlorine gas (Cl₂) in the presence of UV light. This is a radical substitution reaction rather than a nucleophilic substitution.
Step 2
Step B
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Answer
In Step B, ethyl chloride (CH₃CH₂Cl) reacts with sodium hydroxide (NaOH) to form ethanol (CH₃CH₂OH). This step involves nucleophilic substitution, where the hydroxide ion (OH⁻) acts as a nucleophile attacking the carbon attached to the chlorine.
Step 3
Step C
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Answer
In Step C, the reaction of ethanol with sulfuric acid (H₂SO₄) involves dehydration (elimination) to form ethylene (CH₂=CH₂). This step is not a nucleophilic substitution.
Step 4
Step D
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Answer
In Step D, the starting compound BrCH₂CH₂Br undergoes a halogenation reaction with Br₂, forming further alkenes. This is also not a nucleophilic substitution reaction.
