ECAT Chemistry — Alkyl Halides and Amines
Alkyl Halides and Amines is part of the Chemistry section of the UET ECAT (30 of the 100 MCQs). It breaks into 2 subtopics, and we hold 15 ECAT-pattern practice MCQs on it, each with a written explanation. Tap a subtopic below to practise just that.
Subtopics (2)
How Alkyl Halides and Amines is tested
Across the 7 ECAT past papers on ParhaiKrlo, Alkyl Halides and Amines accounts for 6 questions. It appears in 4 of them, about 1.5 questions a paper. The heaviest was ECAT Past Paper 01, with 3 questions, and the most recent is ECAT Past Paper 05, with 1.
| Paper | Questions |
|---|---|
| ECAT Past Paper 05 | 1 |
| ECAT Past Paper 03 | 1 |
| ECAT Past Paper 02 | 1 |
| ECAT Past Paper 01 | 3 |
Alkyl Halides and Amines MCQs from the ECAT past papers
Try each one before opening the answer. Each comes with a short explanation.
- Q1 · ECAT Past Paper 05 · Alkyl Halides and Amines
The reaction CH₃Br + OH⁻ → CH₃OH + Br⁻ is best described as:
- A.Electrophilic substitution
- B.Nucleophilic substitution, bimolecular (SN2)
- C.Nucleophilic substitution, unimolecular (SN1)
- D.Addition reaction
Show answer
Answer: B. Nucleophilic substitution, bimolecular (SN2) — OH⁻ (a nucleophile) replaces Br⁻ on a methyl halide in one concerted step: SN2.
- Q2 · ECAT Past Paper 03 · Alkyl Halides and Amines
Which of the following is NOT an alkyl halide?
- A.Cl–CH₂–Cl
- B.CH₃–Cl
- C.CH₃–CH₂–Br
- D.CH₃–CH₂–OH
Show answer
Answer: D. CH₃–CH₂–OH — CH₃CH₂OH is ethanol, an alcohol; it contains no halogen.
- Q3 · ECAT Past Paper 02 · Alkyl Halides and Amines
Sodium reacts with alkyl halides in dry ether to form alkanes. The reaction is known as:
- A.Wurtz synthesis
- B.Grignard reaction
- C.Both
- D.None
Show answer
Answer: A. Wurtz synthesis — 2RX + 2Na → R–R + 2NaX in dry ether is the Wurtz reaction.