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When OXIDISED with strong oxidising agents like acidified $\mathrm{KMnO_4}$, the product of a PRIMARY alcohol is
Aa KETONE (no further oxidation)
Ban ESTER, formed directly with itself
Can ETHER, with intermolecular water loss
Dan aldehyde, then a carboxylic acid
Answer & Solution
Correct answer: D. an aldehyde, then a carboxylic acid
1. NCERT §7.4 (Oxidation of alcohols): the oxidation product depends on the alcohol's class AND the reagent strength.
2. PRIMARY alcohol ($\mathrm{R{-}CH_2OH}$): with MILD oxidants (e.g. PCC) → aldehyde $\mathrm{R{-}CHO}$, stops there. With STRONG oxidants (acidified $\mathrm{KMnO_4}$, $\mathrm{K_2Cr_2O_7}$): aldehyde is further oxidised to CARBOXYLIC ACID $\mathrm{R{-}COOH}$.
3. SECONDARY alcohol ($\mathrm{R_2CHOH}$): gives a KETONE $\mathrm{R_2C{=}O}$. Cannot be oxidised further without breaking C-C bonds.
4. TERTIARY alcohol ($\mathrm{R_3COH}$): RESISTS oxidation — no H on the OH carbon for removal.
5. Option A correctly describes the primary alcohol path. Option B is the secondary alcohol result. Options C and D describe unrelated reactions.
_Source: NCERT Class 12 Chemistry Part 2, Ch 7, §7.4 (Oxidation of alcohols), p. 13–14._
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