CBSE Class 12 · 2011 · All India · Aldehydes Ketones and Carboxylic AcidsLong Answer

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i) Give chemical tests to distinguish between the following:
a) benzoic acid and ethyl benzoate
b) benzaldehyde and acetophenone
ii) Complete each synthesis shown in the figure (parts a, b, c) by giving the missing reagents or products.

Solution

(i)(a) Benzoic acid liberates CO

_{2}

from NaHCO

_{3}

; ethyl benzoate does not (ester, neutral).
(b) Acetophenone (CH

_{3}

CO–) gives yellow CHI

_{3}

with I

_{2}

/NaOH; benzaldehyde instead gives the Tollens' silver mirror.
(ii) For each printed line supply the missing member by its standard transformation (Rosenmund → aldehyde; alkaline KMnO

_{4}

→ acid; named condensation → its product) as the figure's other two members dictate.

CBSE Class 12 Board · 2011 · All India · Subjective

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