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Which is the correct order… (Class 12 Chemistry 2025, Q8)

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ChemistryCBSE Class 12 · Board exam 2025, set 56/1/1 · 1 mark · MCQ

CBSE Class 12 Chemistry 2025: question 8

Set in the CBSE Class 12 board exam of 2025, paper 56/1/1, section A, question 8, for 1 mark. Try it first; the hints and our step-by-step solution are below.

Q8 · 1 mark · MCQAlcohols, Phenols and Ethers

Which is the correct order of acid strength from the following ?

  1. (A)
  2. (B)
  3. (C)
  4. (D)

Source: official question paper from cbse.gov.in (PDF). See it in the full 2025 board paper, set 56/1/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Compare how stable each conjugate base is.

Hint 2

Consider resonance in phenoxide and the +I effect of R in alkoxide.

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. Phenoxide ion is stabilised by resonance, so phenol is the strongest acid of the three.

  2. The +I effect of the alkyl group destabilises alkoxide, so an alcohol is weaker than water. The order is , option (A).

    1 mark

Answer: C₆H₅OH > H₂O > ROH, option (A)

Where the marks are

  • Chooses the correct order (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Alcohols, Phenols and Ethers, one at a time, marked against the answer key and marking points.Back to the full paper2025 board paper, set 56/1/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.