Chem 112-internal 2004

Universal Science College Internal Examination Subject: Chem 112 (Organic Chemistry) Date: Feb 10, 2005

(B. Sc. Biochemistry) First Semester 2005

Full Marks: 100 Pass Marks: 45 Time: 3 hours

Candidates are required to give their answers in their own words as far as practicable. The figure in the margin indicates the full marks. Group A Long Questions (Any three) 1. (a) Predict the proportions of isomeric products from chlorination at room temperature of (i) n-butane (ii) Isobutane (b) In SN1 reaction, "Reaction proceeds with racemization plus some net inversion". Explain. 2. Discuss the mechanism, orientation and reactivity of bimolecular elimination reaction. 3. Discuss the kinetic and non-kinetic methods of determining reaction mechanism giving examples. 4. Discuss fully the conformational analysis of 1,2- dimethylcyclohexane. Group - B Short Questions: (Any six) 1. Discuss Williamson synthesis. 2. Explain the coupling of alkyl halides with organometallic compounds. 3. Explain the Markovnikov's rule with example. 4. Write down the methods of preparation of alkenes with example. 5. Explain the structure, generation and reaction of carbene intermediate. 6. Describe the types of organic reactions. 7. Explain the optical isomerism of lactic acids. 8. Explain the specification of R and S configurations. Group – C Write short notes on: (Any eight) 1. Rate of chemical reaction can be expressed as a product of three factors. What are they? 2. Write down the two major advantages of carbohydrates. 3. Pyrolysis. 4. Ozonolysis 5. Structure of ethylene 6. Define specific rotation of a compound. 7. What do you understand by angle strain. 8. Give example of geometrical isomerism. 9. Define transition state. 10. What is a functional group. 11. Give one example of a electrophile and a nucleophile. CH3 | 12. CH3 – C – CH = CH2

, H 2O N 2 BH 4 Hg ( OAc )2 →  →

| CH3 3,3 – Dimethyl – 1 – butene ***

?

(3× ×14 = 42)

(6× ×7 = 42)

(2× ×8 = 16)