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When diethyl ether (CH3CH2-O-CH2CH3) is treated with 2 equivalents of HBr at room temperature, what is the major product?

medium 2 marks Class 12 · Chemistry · Alcohols Phenols and Ethers
Answer
2 equiv of ethyl bromide (CH3CH2Br)

The correct answer is 2 equiv of ethyl bromide (CH3CH2Br) — Balanced equation: (CH3CH2)2O + 2 HBr → 2 CH3CH2Br + H2O.

Step-by-step solution

  1. Protonate the ether oxygen with HBr forming an oxonium ion.
  2. The Br- ion attacks the more substituted carbon of the oxonium ion.
  3. Cleavage occurs, producing two molecules of ethyl bromide.
  4. Water is formed as a by‑product.
  5. Balanced equation: (CH3CH2)2O + 2 HBr → 2 CH3CH2Br + H2O.
Common mistake: Using only one equivalent of HBr instead of two

Concept tested: Cleavage of ethers by HBr

Published · How this solution was prepared and checked

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