Question

An organic compound "X" forms an orange-yellow precipitate with 2,4-DNP reagent. It does not react with aqueous [Ag(NH₃)₂] NO₃. X on reduction with NaBH₄ gives a secondary alcohol and on oxidation with nitric acid yields a dicarboxylic acid containing the same number of carbon atoms. On bromination, X gives a monobromo product. On the basis of these reactions, it can be concluded that X 

I. contains aldehydic carbonyl group. 

II. contains ketonic carbonyl group. 

III. contains ester carbonyl group. 

IV. does not contain C=C bonds. 

(A) I only 

(B) III and IV 

(C) III only 

(D) II and IV

Answer 1

Correct answer is (D) II and IV

An organic compounds 'X' forms and orange yellow precipitate with 2, 4-DNP reagent but does not react with aqueous [Ag(NH₃)₂] NO₃ confirms presence of group in form of ketone.

'X' on reduction with NaBH₄ gives secondary alcohol again suggests presence of ketone. 

'X' on bromination gives mono bromo product which suggests absence of bond because in presence of  dibromo product would have been formed.