A compound C9H10O gives an orange precipitate with 2,4-DNP, does not give a silver mirror with Tollens reagent and gives no yellow precipitate with NaOH/I2. Vigorous oxidation with hot alkaline KMnO4 followed by acidification gives benzoic acid. The compound is

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A compound $C X_{9} H X_{10} O$ gives an orange precipitate with 2,4-DNP, does not give a silver mirror with Tollens reagent and gives no yellow precipitate with $NaOH / I X_{2}$ . Vigorous oxidation with hot alkaline $KMnO X_{4}$ followed by acidification gives benzoic acid. The compound is

A1-phenylpropan-2-one
B3-phenylpropanal
C1-phenylpropan-1-one
D1-(4-methylphenyl)ethan-1-one

Answer: C

The compound is a ketone or aldehyde (DNP). Negative Tollens rules out 3-phenylpropanal, and negative iodoform rules out the methyl ketones 1-phenylpropan-2-one and 4-methylacetophenone. Propiophenone,

C X_{6} H X_{5} COCH X_{2} CH X_{3}

, has one side chain and so gives benzoic acid. It fits all observations.

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A compound CX9​HX10​O gives an orange precipitate with 2,4-DNP, does not give a silver mirror with Tollens reagent and gives no yellow precipitate with NaOH/IX2​. Vigorous oxidation with hot alkaline KMnOX4​ followed by acidification gives benzoic acid. The compound is

Answer: C

More questions on Structure determination from reaction sequences

A compound $C X_{9} H X_{10} O$ gives an orange precipitate with 2,4-DNP, does not give a silver mirror with Tollens reagent and gives no yellow precipitate with $NaOH / I X_{2}$ . Vigorous oxidation with hot alkaline $KMnO X_{4}$ followed by acidification gives benzoic acid. The compound is