Chemistry NCERT Exemplar Solutions Class 12th Chapter Twelve

When liquid 'A' is treated with a freshly prepared ammoniacal silver nitrate solution, it gives bright silver mirror. The liquid forms a white crystalline solid on treatment with sodium hydrogensulphite. Liquid 'B' also forms a white crystalline solid with sodium hydrogensulphite but it does not give test with ammoniacal silver nitrate. Which of the two liquids is aldehyde? Write the chemical equations of these reactions also. 

Write down functional isomers of a carbonyl compound with molecular formula C₃H₆O. Which isomer will react faster with HCN and why? Explain the mechanism of the reaction also. Will the reaction lead to the completion with the conversion of whole reactant into product at reaction conditions? If a strong acid is added to the reaction mixture what will be the effect on concentration of the product and why?

An aromatic compound 'A' (Molecular formula C₈H₈O]) gives a positive 2, 4-DNP test. It gives a yellow precipitate of compound 'B' on treatment with iodine and sodium hydroxide solution. Compound 'A' does not give Tollen's or Fehling's test. On drastic oxidation with potassium permanganate it forms a carboxylic acid 'C' (Molecular formula C₇H₆O₂), which is also formed along with the yellow compound in the above reaction. Identify A, B and C and write all the reactions involved.

An alkene 'A' (Mol. formula C⁵H¹⁰ on ozonolysis gives a mixture of two compounds 'B' and 'C'. Compound 'B' gives positive Fehling's test and forms an iodoform on treatment with I₂ and NaOH. Compound 'C' does not give Fehling's test but forms an iodoform. Identify the compounds A, B and C. Write the reaction for ozonolysis and formation of iodoform from B and C.

Write the structures of the following compounds.

(i) α-Methoxypropionaldehyde           

(ii) 3-Hydroxybutanal

(iii) 2-Hydroxycyclopentane carbaldehyde   

(iv) 4-Oxopentanal

(v) Di-sec. butyl ketone                                 

(vi) 4-Fluoroacetophenone