Applied Organic Chemistry — DU B.Sc (hons) Chemistry Previous Year Question Papers

(c) All questions are of 15 marks each. 1. (a) Fill in the blanks - 5 (ii) Cholesterol, belongs to the class of .... (iv) Cortisone is a .. hormones. (v) Ergosterol is used for preventing ..... (b) Define analgesic drugs using suitable example and describe their mode of action. (c) What is the medicinal use of Turmeric, write structure of the active ingredient of curcumin. 5 2. (a) Define "Ziegler Natta" catelysts ? Give the mechanism of polymerization of propene using the same. 5 (b) Give the name of the plant from which natural rubber is isolated ? Outline the process in brief for isolating the rubber from this plant. 5 (c) Give the name of the monomers) for the preparation of the following polymers: (iii) Cellulose 3. (a) a Naphthyl amine on heating with H,SO, at 160°C gives compound (A). Benzidine on diazotization produces compound (B). Coupling reaction of compound (A) and Compound (B) gives Compound (C), Compound (C) is a direct red dye and absorbs Write the complete sequence of reaction from (A) to (C) wih all the reagents used in the reactions. 5 (b) Give one synthesis of Indigo dye and explain it is fixed to the fabric? 5 (c) Define a. Chromophore, b. Auxochrome with examples. 5 4. (a) What is Colour Index (CI) and why is it important in the classification of dyes pigments? 5 (b) (i) If a dye is labeled with the generic name CI Vat Blue 6, what is its Application Type, Hue, and Identifying (ii) Identify the colorant of the above dye and suggest its industrial applications. (c) Discuss natural edible dyes, providing examples and explain the impact of synthetic food colors on health. 5 5. (a) Write the names and biological importants of the following compounds : 2×5=10 (b) Out line the step involved in Emde's modification by taking isoquinoline as an example ? 5 6. (a) An acyclic terpenoid (A), C,0H,60, absorbs two moles of H, and with AgO it oxidized to corresponding carboxylic acid (B) without loss of carbon. Hot alkaline KMnO, treatment followed by CrO, oxidation cleaves (A) into oxalic acid, acetone and 4-keto pentanoic acid. Name and deduce the structure (A) and (b) What is Isoprene rule ? Indicated the isoprene units in the following structure: (c) What are terpenoids and how are they classified ? Discuss any one process for the isolation of essential oil. 5 7. (a) Calculate the number and weight average molecular weights of polymer of sample containing 10 moles of molecular weight 10,000 of polymer A, 80 moles of molecular weight 50,000 of polymer B and 10 moles of molecular weight 1,00,000 of polymer C. (b) Discuss the process of Vulcanization and draw the structure of vulcanized rubber. (c) What are syndiotactic, atactic and isotactic polymers ? Explain using one example. 8. (a) Complete the reaction. Write the structures and names corresponding to A,B, C and D. Give pharmaceutical use of the resulting drug. (b) Match the following : 5 (i) Vitamin C (a) Antimalarials (iii) Ranitidine (c) Rheumatoid arthritis