Preparation of Organic Compounds Viva Questions with Answers

Preparation of Organic Compounds Viva Questions with Answers

Question.1. What is Claisen-Schmidt reaction ?
Answer. It is the condensation of aromatic aldehydes with aliphatic ketones (or aryl alkyl ketones) in the presence of dil. NaOH solution.

Question.2. What is IUPAC name of acetanilide ?
Answer. Phenylethanamide.

Question.3. What is the function of zinc dust in the preparation of acetanilide ?
Answer.

1. It reduces the coloured impurities present in aniline.
2. It prevents oxidation of aniline during the reaction.

Question.4. Give the formula of 2-naphthol aniline dye.
Answer.

Question.5. What is the colour of 2-naphthol aniline dye ?
Answer. Orange-red.

Question.6. What is diazotisation reaction ?
Answer. It is the reaction of primary aromatic amines with nitrous acid to form diazonium salt. The reaction is carried out at low temperature (below 5°C)

Question.7. What is coupling reaction ?
Answer. It is the reaction of diazonium salts with highly activated benzene rings such as phenolic ring. The reaction involves electrophilic substitution and the product obtained is generally a dye.

Question.8. Which of the following compounds on diazotisation followed by compling with β-naphthol will form an azo dye ?
(i) p-Toluidine (ii) Benzylamine (iii) N-Methylaniline
Answer. p-Toluidine, because it is a primary aromatic amine.