BSc Sem V 2023 2024 Jan 2024 CHEMISTRY ORGANIC CHEMISTRY Question Paper - Mumbai University | munotes

Questions asked in this paper

• (2) Figures to the right indicate full marks

1. Q1 Attempt ANY FOUR of the following:
   • A) What is saponification? Explain its mechanism. 5
   • B) List the characteristics of pericyclic reactions. Explain cycloaddition 5 reactions with suitable examples
   • C) Distinguish between:
2. Q1 acidity and electrophilicity li) transition state and intermediate 2 3 marks
   • D) What does NGP stand for? Explain with a suitable example its effect on 5 stereochemical outcome and kinetics of the reaction
   • F) What is a photochemical reaction? Explain di-a-methane reaction. 5
3. Q2 Attempt ANY FOUR of the following:
   • A) Write a note on the following- 5
   • a) Plane of symmetry
   • b) Centre of symmetry
   • B) Explain the optical isomerism in cumulenes with even number of double 5
   • C) Give the Skraup synthesis for the preparation of quinoline. Write the reaction 5 of quinoline with the nitrating mixture
   • D) What is the action of following reagents on given heterocyclic compounds? 5
   • b) on pyridine-N-oxide
   • c) in on pyridine-N-oxide
   • E) What are Agrochemicals? Give two advantages of it. Write the synthesis of 5
   • F) a) What are the properties of ideal pesticides? 3
   • b) Draw the resonating structure of pyridine-N-Oxide 2
4. Q3 Attempt ANY FOUR of the following:
   • A) Write the structural formula for each of the following compounds: 5
5. Q2 acid
6. Q3 1-methylspiro [3.3] heptane
7. Q5 1-chloro-1,2-pentadiene
   • B) Give the IUPAC names of the following: 5
   • C) a) Explain Linear synthesis with a suitable reaction? 3
   • b) Give an example of regioselectivity? 2
   • D) Give the synthesis of the following from a suitable starting compound? 5
8. Q2 p-nitroaniline from aniline
   • E) a) Calculate the percentage atom economy for the following reaction? 3
   • b) Give the use of dimethyl carbonate as a selective methylating agent 2
   • F) a) Explain multicomponent reaction with a suitable example? 3
   • b) How is theoretical yield calculated? 2
9. Q4 Attempt ANY FOUR of the following:
   • A) a) Explain Chromophore theory in UV-visible spectroscopy 3
   • b) Explain effect of solvent in UV-visible spectroscopy. 2
   • B) a) Explain the mass spectral fragmentation pattern of ethyl methyl ketone 3
   • b) Give the importance of molecular ion peak. 2
   • C) a) Give analytical evidence to prove the following:
10. Q1 Citral is an acyclic monoterpenoid 3 marks
11. Q2 The presence of an aldehydic group in Citral
    • b) What is Geminal dialkyl rule ? 2
    • D) Give the synthesis of Nicotine from Nicotinic acid. 5
    • E) a) Complete the following reaction 3
    • b) Write the structures of Geranial and Neral. 2
    • F) a) Give Ott’s synthesis of adrenaline 3
    • b) What are the harmful effects of Nicotine? 2
12. Q5 A) Select the correct option and complete the following statements: (ANY 5 marks
    • a) Thermal decomposition of . having B-hydrogen to form alkenes is
    • b) Acid catalysed esterification is a .reaction that follows
    • c) The products of Cope elimination are
    • d) . 1s an electron deficient species that attacks at positions of
    • e) . reactions involve formation of two sigma bonds to the same carbon
    • f) Phosphorescence has .wavelength and . energy than
    • g) Photochemical conversion of benzophenone to benzpinacol is an example of
    • h) Carbonyl compounds having Y-hydrogen under photolytic conditions prefer to undergo . reaction
    • B) State whether the following statements are TRUE or FALSE: (ANY 5
    • a) Cumulenes with even number of double bonds and unsymmetrical substitution on terminal carbons will not show optical isomerism
    • b) Always an optically active compound must contain at least one chiral carbon
    • c) Centre of symmetry is also known as Inversion Centre
    • d) In quinoline electrophilic substitution takes place at position 2
    • e) Glycerol is reactant used in Skraup quinoline synthesis
    • f) The dipole movement of pridine-N-oxide is more than pyridine
    • g) Fungicides are the chemicals that destroy, prevent or inhibit the growth of
13. Q5 C) Fill in the blanks with the correct alternative given in the bracket: 5 marks
    • a) In Bicyclo [ 4.2.1] nonane, there exists number of carbon atom between the two bridged carbon atoms
    • b) In 6-chlorospiro [4.5] decane , the substitution is on the ring
    • c) Allene has .cummulative double bonds
    • d) Petroleum is an example of ----------- fuel
    • e) -------- reagents are superior to stoichiometric reagents
    • f) Reactions with lower ---------- are desirable
    • g) of atom economy was developed by
    • h) Liquid CO, is an example of a ---------- solvent
    • D) Match the columns and rewrite the matched pairs: (ANY FIVE) 5
    • a) Citral (i) Highest peak in mass
    • g) of absorption to lower wavelength (vii) Ductless glands

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