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Benzaldehyde is treated with concentrated $\mathrm{NaOH}$ (Cannizzaro reaction). The products are:

ASalicylaldehyde and water
BSodium benzoate and benzyl alcohol
CBenzoic acid only
DBenzyl alcohol only
Answer & Solution
Correct answer: B. Sodium benzoate and benzyl alcohol
**Cannizzaro reaction** is the disproportionation of an aldehyde with **no $\alpha$-hydrogen** under concentrated alkali. One molecule of the aldehyde is oxidised, one is reduced. For benzaldehyde + NaOH (conc.): - One PhCHO is *oxidised* to PhCOO⁻Na⁺ (**sodium benzoate**). - One PhCHO is *reduced* to PhCH₂OH (**benzyl alcohol**). So the product mix is option C. Acidifying the workup converts the sodium benzoate to benzoic acid, but the raw Cannizzaro products are as written. **Why option A is wrong on its own.** Plain oxidation of benzaldehyde with stronger oxidants gives benzoic acid alone; that's *not* Cannizzaro — Cannizzaro requires the simultaneous reduction half.
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