M.Sc. Chemistry (Previous) DEGREE EXAMINATION, DECEMBER Paper I - GENERAL CHEMISTRY. Answer ALL questions UNIT I

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1 (DCHE 01) M.Sc. Chemistry (Previous) DEGREE EXAMINATION, DECEMBER Paper I - GENERAL CHEMISTRY Answer ALL questions UNIT I 1. (a) Explain briefly the origin of any four types of molecular spectra. (10) (b) Discuss the allowed transitions in the rotational energy levels of molecules. (10) 2. (a) (i) Give an account of isotopic effect in rotational spectra. (7) (ii) Describe the spectra of rigid and nonrigid rotor systems. (8) (b) (i) What are the sources of radiation and detectors used in recording the NMR and ESR spectra of molecules. (7) (ii) Give an account of microwave spectra of linear molecules. (8) UNIT II 3. (a) Explain the origin of electronic spectra of molecules. (10) (b) Give an account of vibrational energy levels and transitions of a diatomic molecule. (10) 4. (a) Give an account of vibrational structure of an electronic transition. (15) (b) Discuss the vibrational and rotational spectra of diatomic molecules. (15) UNIT III 5. (a) Give the importance of samping techniques used for different forms of substances. (10) (b) Explain the importance of Accuracy and Precision in analytical determinations. (10) 6. (a) Discuss the types of errors encountered in chemical analyses. (15) (b) What is meant by mean, median, average deviation relative deviation and standard deviation? Calculate the above parameters for the following data. The normality of a solution determined by four individuals is, , , and (15)

2 UNIT IV 7. (a) Compare the features of mainframe, micro and super computers. (10) (b) Describe the format of different assignment statements used in FORTRAN. (10) 8. (a) Write a FORTRAN program to calculate the rate constant of a first order reaction from the observed kinetic data. (15) (b) Write a FORTRAN program to calculate and print the pressure of a vander Waal s gas, given the volume, temperature and vander Waal s constants. (15) (DCHE 02) M.Sc. Chemistry (Previous) DEGREE EXAMINATION, DECEMBER Paper II - INORGANIC CHEMISTRY Answer ALL questions. UNIT - I 1. (a) What is black body? Explain the effect of temperature on black body radiation. (10) (b) Discuss the Heisenberg s uncertainty principle. (10) 2. (a) (i) Give an account of Larmor precessional motion of orbit-angular momentum. (10) (ii) Write the term symbols for p 3 and d 2 configurations. (5) (b) (i) Write a note on atomic spectra of alkali meatals. (8) (ii) Explain L-S and J-J coupling an molecules. (7) UNIT - II 3. (a) Define lattice energy and calculate the lattice energy of NaCl using Born-Haber cycle.(10) (b) What are the types of solids? Explain them with suitable examples. (10) 4. (a) What is LCAO? Explain the salient features of MO theory and construct MO Diagram for CO + molecule. Discuss the stability of CO, N 2, N 2 based on bondorder. (15) (b) Explain the valence bond approach in determining the bonding in hydrogen (H 2 ) molecule.(15)

3 UNIT III 5. (a) (i) Describe the Job s method for the determination of stability constant of a complex. (5) (ii) What are the factors that effect the stability of a complex? (5) (b) Describe the John-Teller effect on geometry of octahedral complexes with suitable examples. (10) 6. (a) (i) Explain the magnetic and geometry nature of outer and inner orbital complexes based on VBT. (10) (ii) Anhydrous CuSO 4 is colourless where as hydrated CuSO 4 is blue. Explain. (5) (b) Write a note on the following : (i) Spectrochemical series (5), (ii) crystal field stabilization energy (CFSE) (5), (iii) Chelate effect (5). UNIT IV 7. (a) How do you explain ability and inertness of coordination compounds based on VBT and CFT? (10) (b) Discuss the structure and bonding of metal nitrosyls with suitable examples. (10) 8. (a) (i) Explain SN CB mechanism with suitable example. (10) (ii) The electron transfer from [ ] to [ ] is very rapid. What is the reason? (5) [ ] (b) (i) How is transeffect useful in the synthesis of cis and trans ( ) from the appropriate starting material. Discuss the different theories proposed for explaining the transeffect. (10) (ii) write a short note on silicones. (5)

4 (DCHE 03) M.Sc. Chemistry (Previous) DEGREE EXAMINATION, DECEMBER Paper III - ORGANIC CHEMISTRY Answer ALL questions 1. (a) Explain Huckel s rule and its limitations. Discuss the modern concept of aromaticity with suitable examples. (10) (b) Write a note on the following : (i) Alternant and non-alternant hydrocarbons (5), (ii) Aromatic character of azulenes.(5) 2. (a) (i) Discuss optical activity of allenes. (8) (ii) Explain the terms stereo specific and stereo selective synthesis with suitable examples. (7) (b) (i) What is asymmetric synthesis? Describe an asymmetric synthesis using a chiral catalyst. (8) (ii) Explain why trans 1, 3-di-t-butyl cyclohexane prefers a boat conformation. (7) 3. (a) Write a brief explanatory notes on the following : (i) Kinetically and thermodynamically controlled products (5), (ii) Isotopic Labelling. (5) (b) Discuss the formation and reactions of carbenes. 4. (a) Discuss neighbouring group participation with suitable examples. (15) (b) Explain different factors which influence the nucleophilic substitution reaction to proceed by either SN 1 mechanism or SN 2 mechanism. (15) 5. (a) Write short notes on : (i) Free radical aromatic substitution (5), (ii) Autoxidation (5) (b) Discuss the generation, stability and addition reactions of free radicals. (10) 6. (a) Write the mechanistic and stereochemical aspects of addition reactions involving electrophiles and nucleophiles. (15) (b) Write short notes on : (i) Free radical rearrangements (5), (ii) Hydroboration (5), (iii) Michael reaction (5)

5 7. (a) Write brief notes on : (i) Witting reaction (5), (ii) Benzoic condensation (5). (b) Write the mechanism of Perkin reaction and Knoevenagel reactions with suitable examples. (10) 8. (a) Discuss the mechanism and orientation in pyrolytic eliminations. (15) (b) Write notes on the following. (i) The Saytzeff and Hofmann rules (8), (ii) E 2 mechanism (7). (DCHE 04) M.Sc. Chemistry (Previous) DEGREE EXAMINATION, DECEMBER Paper IV - PHYSICAL CHEMISTRY Answer All Questions 1. (a) Define the entropy of a system. Explain the entropy changes in reversible and irreversible process. (10) (b) Explain the significance of Gibbs and Helmholtz free energies? Derive Gibbs Helmholtz equation? 2. (a) Explain partial molar properties? Derive Gibbs Duhem equation. (b) Derive thermodyanamic derivation of phase rule and Raoult s law. (15) 3. (a) What are Miller Indices? Explain (100), (110) and (111) planes for a cubic crystal? (10) (b) Explain the measurement of radioactivity by G.M. Counters and scintillation counters. 4. (a) Explain the defects in crystals? Write a note on Schottky and Frenkel defects and measurement of lattice energy? (15) (b) What is radioactive disintegration level and radioactive equilibrium? Derive the relationship between Decay constant and half-life period of a radioactive element? 5. (a) Explain the differences between physical adsorption and chemisorption. Derive Langmuir adsorption isotherm. (10)

6 (b) What are micelles? Explain the micellar mechanism with on e example. Mention different types of micelles with examples. 6. (a) Derive Nernest equation for an electrochemical cell. Explain the relationship between E.m.f. of a cell and DG. (b) Give examples of concentration cells with and without transference and explain the cell reactions with one example. (15) 7. (a) Discuss the absolute reaction rate theory. Mention its applications. (10) (b) Derive First order rate expression for complex reactions. 8. (a) Discuss the protolytic and prototropic mechanisms of acid-base catalysis. (b) Write short notes on : (i) Jablonski diagram, (ii) Michaelis Menton Kinetics. (DCHE 21) M.Sc. Chemistry (Final) DEGREE EXAMINATION, DECEMBER Paper V - ANALYTICAL CHEMISTRY PART A- (4 x 10 = 40 marks) Answer any FOUR questions 1. Describe in detail the instrumentation of photoelectric colorimeter. 2. What are the differences between nephelometry and turbidimetry? Mention the applications of turbidimetry. 3. Define the terms fluorescence and phosphorescence. Write the applications and limitations of phosphorimetry. 4. Explain the principle and theory behind atomic absorption spectroscopy. What are its merits and demerits? 5. State and explain Poggendorff s principle. Write the advantages of potentiometric titrations over ordinary indicator methods. 6. Write in detail on amperometric titrations. 7. Give an account on the principles of solvent extraction.

7 8. What is meant by ion exchange? Explain with examples. How can you use this technique in water treatment? PART B (4x15 = 60 marks) Answer ALL questions 9. (a) (i) Explain in detail about the basis of colorimetry. (ii) Give an account of base line method in IR spectroscopy. (b) Write a note on the applications of colorimetry with particular reference to phosphate and iron (Fe 2+ and Fe 3+ ) 10. (a) (i) What are the factors affecting fluorescence and phosphorescence? (ii) What are the various types of errors occur in flame photometry? (b) (i) Explain in detail the applications of atomic absorption spectroscopy. (ii) What is quenching? Explain. 11. (a) Narrate the applications of conductometry with reference to (i) Precipitation titrations (ii) Determination of solubility of sparingly soluble salt and, (iii) Ionic product of water. (b) Write short notes on the construction of (i) Hydrogen electrode and, (ii) Quinhydrone electrode. 12. (a) (i) Explain the principle involved in paper chromatography. (ii) Narrate the extensively about radial paper chromatography. (b) Describe the principle, theory and instrumentation of gas chromatography. (DCHE 22) M.Sc. Chemistry (Final) DEGREE EXAMINATION, DECEMBER Paper VI - INORGANIC CHEMISTRY PART A- (4 x 10 = 40 marks) Answer any FOUR questions 1. What are the different oxidation states exhibited by actinides? Explain. 2. Why lanthanides and actinides give sharp absorption peaks compared to transition elements?

8 + [ ] 3. Discuss the absorption spectrum of ( ) 4. Write a note on overtones and combination bands. 5. What are the different types of magnetic behaviour exhibited by materials? 6. Explain the basic principle involved in NMR spectroscopy 7. Discuss the role of calcium in biological systems. 8. Write an account on hemerythrins and hemocyanins. PART B (4 x 15 = 60 marks) Answer ALL questions. 9. (a) (i) What is an actinide contraction. (ii) Discuss any two methods for the separation of actinides. (b) (i) Discuss the spectrophotometric method for the determinations of the composition of a complex. (ii) Why is dark purple and is bright yellow in color? Explain. 10. (a) (i) Explain the theory of Raman effect. (ii) Discuss the applications of Raman spectroscopy in the structural elucidation of inorganic compounds. (b) Describe different methods of crystal growth for X-ray diffraction studies. 11. (a) (i) How the ESR spectroscopy is different from NMR spectroscopy? (ii) Discuss the applications of ESR in the study of inorganic compounds. (b) (i) What is spin-spin coupling in NMR spectroscopy? (ii) What is the principle involved in mass spectrometry? Write an account on general rules governing fragmentation of molecules in mass spectrometry. 12. (a) (i) Discuss the toxicity of cadmium and lead in living systems. (ii) Write an account on the mechanism of oxygen transport by myoglobin and haemoglobin. (b) Write notes on : (i) Ionophores (ii) Chelation therapy.

9 (DCHE 23) M.Sc. Chemistry (Final) DEGREE EXAMINATION, DECEMBER Paper VII - ORGANIC CHEMISTRY PART A- (4 x 10 = 40 marks) Answer any FOUR questions 1. (a) Explain in detail about the electronic excitation in UV spectroscopy. (b) How would you distinguish cis-and trans-cinnamic acid by UV-visible spectroscopy? 2. How would you distinguish the following sets of compounds using IR spectra? (a) Cyclohexanol and cyclopentanol, (b) Primary, Secondary and Tertiary amines (c) Esters and Lactones, (d) Mono-and di-substituted benzene. 3. Explain the principles of spin-spin interaction of protons in NMR spectroscopy. 4. Write short notes on the following : (a) Nitrogen rule, (b) Meta stable peak. 5. (a) What is quantum yield? Explain (b) Explain Norrish type II reaction with suitable mechanism. 6. Give an account on the electrocyclic reactions. 7. What are the alkaloids? Describe the general methods of structure determination of alkaloids. 8. Write short notes on the following : (a) Baeyer-Villiger rearrangement (b) Neber rearrangement PART B (4 x 15 = 60) marks Answer all the Questions 9. (a) (i) Calculate the λ for the following compounds } } ACO (b) (ii) Narrate the dieve absorption in UV spectroscopy. (i) Describe about the instrumentation (FIIR) of IR spectroscopy. (ii) Write short notes on finger print region in IR spectra

10 10. (a) Write short notes on the following : (i) Chemical exchange, (ii) Nuclear over Hauser effect (b) Acetaldehyde (in CpCl 3 and TMS) shows a quartet at δ and a doublet at δ in its PMR spectrum, while in D 2 O it shows in addition, a doublet of a doublet at δ and a doublet at δ. Account for these observations. (c) (i) Write a note on β cleavage in mass spectrometry. (ii) The mass spectrum for 1-hexanol gives a base peak at m/z=56. How can one account for this? 11. (a) (i) Discuss the photochemical reactions exhibited by conjugated olefins. (ii) Explain the process of photo sensitization. (b) (i) Discuss the length the shapes and symmetry properties of molecular orbitals with suitable examples. (ii) Give an account on the sigmatropic rearrangements. 12. (a) (i) Describe the total synthesis of Quinine. (ii) Explain the terms isoprene rule and special isoprene rule. Illustrate these rules in interpenoids. (b) Write briefly on : (i) Bechmann rearrangement, (ii) Arndt-Eistert synthesis. (DCHE 24) M.Sc. Chemistry (Final) DEGREE EXAMINATION, DECEMBER Paper VIII - ENVIRONMENTAL CHEMISTRY PART A- (4 x 10 = 40 marks) Answer any FOUR questions 1. What are the different segments in Environment? Describe their functioning and uses. 2. What is pollution? Classify different types of pollution. Describe their sources with suitable example. 3. Classify the different types of anthropogenic air pollutants. Describe their sources and effects on environment.

11 4. Explain the following. (a) Acid Rain (b) Photochemical smog. 5. Write a brief note on the unique properties of water and the different structures of liquid water. 6. (a) What are the USPH and ISI standards of drinking water? (b) What type of properties are considered for boiler feed waters and irrigational water? 7. (a) Describe the Spectrometric determination of Nitrites in a water sample. (b) Wha is the significance of Dissolved Oxygen? Explain. 8. (a) What are COD and BOD? (b) Explain the significance of COD over BOD. PART B (4 x 15 = 60 marks) Answer ALL questions. 9. (a) Write notes on : (i) Receptor, (ii) Sink, (iii) Path way of pollutant, (iv) threshold limit Value. (b) (i) Describe the structure of earth. (ii) What are the different minerals obtained in the earth crust and their importance with reference to metallurgy? 10. (a) (i) What is particulate matter and its chemical composition? (ii) Name at least two devices for the control of particulate air pollution and explain how they work. (b) (i) What are the different sources and sinks for Nitrogen oxides? (ii) Write any two control technologies for minimizing Nitrogen Oxide pollution? 11. (a) (i) Classify the Natural water sources? (ii) Given an account on Hydrological Cycle. (b) (i) What is sea water composition? (ii) Describe different steps involved in the preparation of sea water model. 12. (a) (i) Discuss sample collection procedures for the analysis of different parameters in water samples? What should be nature of containers for sample collection (ii) Given an account on the preservation of samples for the analysis of different parameters in water samples. (b) (i) Describe the Tertiary treatment process for polluted water. (ii) How the Electro dialysis process is used for the purification of water samples?