M.Sc. Chemistry Question paper

Loyola College M.Sc. Chemistry April 2006 Organic Chemistry-II Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 28

SECOND SEMESTER – APRIL 2006

                                                     CH 2801 – ORGANIC CHEMISTRY – II

 

 

Date & Time : 19-04-2006/FORENOON     Dept. No.                                                       Max. : 100 Marks

 

 

Part-A

                                                        Answer ALL questions.       (10 ´ 2 = 20 marks)

  1. Which of the following is a better nucleophile? Why?
    a) Phenol or ethanol             b) nitride or fluoride
  2. ‘Dehydrochlorination of neomenthylchloride gives two different alkenes.’ Explain
  3. ‘endo-anti-tricyclo[3.2.1.02-4]octan-8yl-p-nitrobenzoate is solvolysed 1014 times faster than p-nitro isomer containing C=c’. Explain
  4. Arrange the following in the decreasing order of nucleophilicity. Justify your answer.    OAc–, ClO4–, H2O, p-brosyl, OH–
  5. Pyrolysis of iso-butylacetate gives a mixture of two alkenes in a ration 3:2. Explain with mechanism.
  6. Give any four differences between DNA and RNA.
  7. How are enzymes classified on the basis of their mode of action?
  8. ‘When the leaving group cannot act as a nucleophile, substitution can take place at the bridgehead’. Explain.
  9. Write a note on NADP.
  10. Threo DL pair of 3-bromo-2-butanol with HBr gives DL-2,3-dibromobutane while erythro isomer gives meso. Explain
Part-B

                                                     Answer any eight questions.       (8 ´ 5 = 40 marks)

  1. Solvolysis of syn-7-p-anisyl-anti-7-norborn-2-enyl-p-nitrobenzoate in acetone    water is 2.5 times faster than its saturated analog.  Explain.
  2. Acetolysis of both 4-methoxy-1-pentylbrosylate and 5-methoxy-2-pentyl brosylates give the same mixture of products.
  3. Explain the ion-pair involvement in SN1 mechanism. What are the evidences of ion-pair mechanism?
  4. ‘2-octylbrosylate with 75% aqueous acetone gives 2-octanol with 77% inversion but with sodium azide gives 100% inversion’. Explain with mechanism.
  5. Explain the mechanism of Steven’s rearrangement.
  6. Explain the mechanism of Hofmann rearrangement. Is it inter or intramolecular? Explain.
  7. Explain the primary structure of protein.
  8. What are conjugated proteins? How does the protein structure in heamoglobin assist in oxygen transfer?
  9. Explain normal and abnormal Claisen rearrangement with mechanism.
  10. What are the types of RNA? How are they helpful in protein synthesis? Explain.
  11. Explain the immobilization of enzymes.
  12. ‘2-butylacetate on pyrolysis gives a mixture containing 57% 1-butene and
    43% 2-butene.  Explain.
Part-C

                                                        Answer any four questions.      (4 ´ 10 = 40 marks)

  1. a) 2-bromo-2-methylbutane with EtO– gives 70% 2-methyl-2-butene but with
    Et3C-O– gives 12% only. Explain with mechanism.
  2. b) Explain how free radical monobromination of 1-bromo-2-methylbutane yields a product with a high degree of retention in configuration.
  3. a) b-(Syn-7-norbornenyl)ethylbrosylate undergoes acetolysis about 140,000 times faster than its saturated analog. Explain.
  4. b) Explain Swain-Scott relationship with a suitable example.
  5. a) Explain the orientation of double bond in elimination reactions with suitable examples.
  6. b) Pyrolysis of erythro and threo isomers of 1-acetoxy-2-deutero-1, 2-diphenyl ethane gives the same alkene.  Explain with mechanism.
  7. a) What are coenzymes? Explain the various sources of coenzymes and their functions.
  8. b) What are long and short lived free radicals?  How are they prepared?  How are they useful in organic synthesis?
  9. Explain the following
  10. a) Erythro-3-bromo-2-butanol with HBr gives meso product
  11. b) Rate of solvoysis of Ph-CH2-CH2-OTs with 75% CF3COOH is 3040 times faster than CH3-CH2-OTs
  12. c) Solvolysis of exo-2-norbornyl brosylate is 350 times faster than its endoisomer
  13. d) Pyrolysis of xanthates give COS as one of the products.
  14. Explain the following:
  15. a) Ambident nucleophile
  16. b) Fischer-Indole synthesis
  17. c) Allosteric enzymes

 

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Loyola College M.Sc. Chemistry April 2006 Nuclear & Solid State Chemistry Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 43

FOURTH SEMESTER – APRIL 2006

                                    CH 4952 – NUCLEAR AND SOLID STATE CHEMISTRY

(Also equivalent to CH 4802)

 

 

Date & Time : 22-04-2006/9.00-12.00         Dept. No.                                                       Max. : 100 Marks

 

 

Part A

Answer the following                                                                             10×2 = 20

  1. What are unit cell parameters of (i) triclinic (ii) hexagonal?
  2. What is ‘123’ oxide? Mention its significance.
  3. Mention the number of space lattices and space groups in two and three dimensional lattices.
  4. What is piezoelectric effect? Cite two examples of piezoelectric crystals.
  5. Give two examples for organic semiconductors. Cite two advantages of them.
  6. What is the significance of n/p ratio?
  7. How do radio particles come out of the nucleus without spending activation energy?
  8. What is the unique behaviour of 10B? How is this behaviour useful in nuclear reactors?
  9. What is the mechanism of γ – emission?
  10. Show that t1/2 = 693/λ

 

Part B

Answer any eight of the following:                                                       8×5 = 40

  1. Describe the operations that produce improper axis.
  2. Write a note on space groups.
  3. How is photoelectriccatalytic splitting of water carried out?
  4. How are semiconductors used in the photovoltaic cell?
  5. What is Kammerlingh – Onnes experiment? Write a note on Type I superconductors.
  6. Discuss the Debye theory on the heat capacity of solids.
  7. Explain the nature of forces in operating in the nucleii.
  8. Describe ranges of various radio particles.
  9. Why are the mass numbers of stable isotopes of chlorine and copper not continuous but are alternate numbers?
  10. What is hot atom chemistry? Explain Szillard – Charmers process and its application.
  11. What is the principle of neutron activation analysis? What are the disadvantages of this technique?
  12. Write a note on cold fusion.

Part C

 

Answer any four of the following:                                                        4×10 = 40

  1. Describe the one dimensional conducting in (SN)x and partially oxidized [Pt(CN)4]2-.
  2. Discuss the Fourier synthesis in obtaining electron charge density in the crystal structure analysis.
  3. Discuss the iron – thionine and Ru3+– bipyridyl systems in their photovoltaic behaviors.
  4. Discuss the use of nuclear shell model in explaining magic numbers.
  5. How is signal size in a charged particle counter affected by applied potential?
  6. Discuss working of a nuclear reactor.

 

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Loyola College M.Sc. Chemistry April 2006 Nuclear & Radiochemistry Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 35

SECOND SEMESTER – APRIL 2006

                                            CH 2952 – NUCLEAR AND RADIOCHEMISTRY

 

 

Date & Time : 26-04-2006/9.00-12.00         Dept. No.                                                       Max. : 100 Marks

 

 

Part A

Answer the following                                                                             10´2 = 20

  1. What are isotones? Give an example.
  2. What is nuclear quadrupole moment?
  3. Mention the nuclear spin of (a) 12C (b) 2H .
  4. What is internal conversion?
  5. Give the mechanism of positron emission.
  6. How is the odd – even rule useful in predicting stability of a nucleus?
  7. Show that t1/2 = 693/λ
  8. How are thermal neutrons obtained?
  9. What is the final product obtained if 2 α and 4 β– particles are emitted from 236U?
  10. Explain tunneling effect.

Part B

Answer any eight of the following:                                                       8´5 = 40

  1. Write a note on nuclear forces.
  2. Discuss the stability of the nucleus based on n/p ratio.
  3. Discuss the principle of Dempster mass spectrograph.
  4. Write a note on proportional counters.
  5. What is double β decay?
  6. What mass of 14C with t1/2 = 5730y has an activity equal to one curie?
  7. How is radius of a nucleus deduced? Calculate density of 81
  8. What is electron capture? What are its consequences?
  9. Why are the atomic weights of elements found in fraction?
  10. What is the significance of interaction of radiation with water?
  11. What is the principle of isotope dilution analysis? What are the disadvantages of this technique?
  12. Write a note on use of radio isotopes in determination of mechanism of a reaction.

Part C

Answer any four of the following:                                                        4´10 = 40

  1. How is binding energy calculated theoretically using liquid drop model?
  2. Describe the mechanism of β decay emission. Explain the forbidden and allowed transitions of β decay using Kurie plot.
  3. Write a note on (a) Geiger Counter (b) Scintillation counter
  4. Discuss the use of nuclear shell model in explaining magic numbers.
  5. How is the factor binding energy per nucleon significant in deciding stability of a nucleus?
  6. Discuss working of a nuclear reactor.

 

 

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Loyola College M.Sc. Chemistry April 2006 Molecular Spectroscopy Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 33

SECOND SEMESTER – APRIL 2006

                                               CH 2950 – MOLECULAR SPECTROSCOPY

(Also equivalent to CH 2802)

 

 

Date & Time : 21-04-2006/FORENOON     Dept. No.                                                       Max. : 100 Marks

 

 

Part-A   ANSWER ALL QUESTIONS (10 x 2 = 20)

  1. Indicate which one will have higher λmax value and explain
  • CH2 = CH2 and CH2 = CH – CH = CH2
  • C6H6 and C6H5OCH3
  1. The 1H NMR of C4H9Cl gave a single peak at 1.80 δ as a singlet. Give the structure of the compound.
  2. Sketch the EPR spectrum of C6H5• radical and explain.
  3. Which one has a higher ν(C=O) value? Explain

O                                                O

||                                                  ||

CH3 – C – CH3       and    CH2 = CH – C – CH3

  1. How is the mass of metastable peak calculated in the mass spectrum? Explain with one example.
  2. Identify the point groups for the following molecules:

(a)POCl3    (b) SF6     (c) Br2          (d) Ni(CN)42- (square planar)

  1. Explain the rule of mutual exclusion with a suitable example.
  2. Explain the spectroscopic transitions (a) fundamental (b) hot bands using proper quantum
  3. Explain the meaning and significance of x, y, and z in the T2 representation of the Td point group as shown below

Td      E          8C3      3C2      6S4       6σd

T2      3          0          -1         -1         1          (x,y,z)

 

  1. Identify the symmetry operations present in the point groups C1, Ci, and Cs. Give one example for each.


Part-B   ANSWER ANY EIGHT QUESTIONS (8 x 5 = 40)

  1. How does the solvent polarity affect the λmax of the compound?
  2. How are the following differentiated by the infrared spectral studies?
  • aliphatic and aromatic compounds
  • ethanol and diethyl ether (3+2)
  1. Write a note on Nuclear Overhauser effect.
  2. Sketch the Mossbauer spectrum of [Fe(CN)6]3- and explain.
  3. Discuss the detectors used in UV-Visible double beam spectrophotometer.
  4. Discuss the McLafferty rearrangement in the mass spectral fragmentation pattern.
  5. Explain the factors for the broadening of spectral lines.
  6. How are P, Q, and R branches of absorption bands obtained in vibration-rotation spectra of molecules? In which type of molecules Q branch is not observed and why?
  7. (a) When do we say two symmetry operations are in the same class? Explain with an example.
    • The equilibrium vibration frequency of the HBr molecule is 2649.7 cm-1 and the anharmonicity constant is 0.0171; what, at 300K, is the intensity of the ‘hot band’ (v=1 to v=2 transition) relative to that of the fundamental (v=0 to v=1)?    (2+3)
  1. A microwave spectrometer capable of operating only between 60 and 90 cm-1 was used to observe the rotational spectra of HI. Absorptions were measured as follows:
HI (cm-1)
64.275

77.130

89.985

Find B, I and r for each of the molecule, and determine the J values between which transitions occur for the first line listed above.

  1. (a) Explain the following with a suitable molecule for each:

(i) Principal axis of rotation    (b) Inversion Center

(b) Explain the meaning of a Eg representation in the character table.  (2+2+1)

 

 

 

  1. Give the reduction formula and reduce the following reducible representation.

C2h      E          C2        i          σh          

8          0          6          2

 

C2h       E          C2        i           σh

Ag        1          1          1          1          Rz              x2, y2, z2, xy

Bg           1          -1         1          -1         Rx, Ry        xz, yz

Au        1          1          -1         -1         z

Bu        1          -1         -1         1         x, y

 

 

Part-C   ANSWER ANY FOUR QUESTIONS (4 x 10 = 40)

  1. How are the UV-Visible spectral studies useful in (a) charge-transfer transition
    (b) electronic effect in the organic molecules? (5+5)
  2. Describe the following:
  • Proton noise decoupled 13C-NMR
  • Spin-spin coupling in 1H NMR                                                               (5+5)
  1. Discuss the principle and instrumentation involved in the EPR spectroscopy. Explain the nuclear hyperfine splitting. (4+3+3)
  2. (a) State and explain Franck-Condon Principle. How are intensity variations of electronic spectra explained by this principle?

(b) The Bond length of NO is 115.1 pm. Bond force constant is 1595 Nm-1. Calculate (a) Zero-point energy and the energy of the fundamental vibration ν0.
(b) Calculate the rotational constant B. (c) Calculate the wave numbers of the lines P1, P2, R0 and R1                                                                                      (5+5)

  1. (a) What are Stokes and anti-Stokes lines and Rayleigh lines? Compare their intensities in the Raman vibrational spectrum of a compound.

(b) Consider the molecules N2, CCl4, CH3Cl and H2O. Predict which of them will show (a) Pure rotational spectrum (b) infrared absorption (c) electronic transition. Give reasons for your choice.                                                                      (5+5)

  1. Find the number, symmetry species of the infrared and Raman active vibrations of CH4, which belongs to Td point group. State how many of them are coincident.

(You may, if you wish, use the table of f(R) given below for solving this).

 

Operation:      E     σ       i       C2      C3     C4     C5         C6     S3       S4      S5       S6       S8

              f(R):       3     1     -3       -1       0       1     1.618      2      -2        -1     0.382   0     0.414

For any Cn,       f(R) = 1 + 2cos(2π/n),            For any Sn, f(R) = -1 + 2cos(2π/n)

 

 

Td         E          8C3      3C2      6S4       6σd

A1        1          1          1          1          1                                  x2+y2+z2

A2        1          1          1          -1         -1

E          2          -1         2          0          0                                  (2z2-x2-y2, x2-y2)

T1         3          0          -1         1          -1         (Rx,Ry,Rz)

T2         3          0          -1         -1         1          (x,y,z)              (xy,xz,yz)

 

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Loyola College M.Sc. Chemistry April 2006 Instrumental Methods Of Chemical Analysis Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – ZOOLOGY & BIOMEDICAL INSTRUMENTATION

LM 32

SECOND SEMESTER – APRIL 2006

                          CH 2901 – INSTRUMENTAL METHODS OF CHEMICAL ANALYSIS

 

 

Date & Time : 28-04-2006/9.00-12.00         Dept. No.                                                       Max. : 100 Marks

 

 

Part-A   ANSWER ALL QUESTIONS (10 ´ 2 = 20)

  1. Define: (i) a mole   (ii) molarity
  2. If drinking water contains 1.5 ppm of NaF, how many liters of water can be fluoridated with 454 g of NaF?
  3. Explain hypsochromic shift with an example.
  4. Sketch and explain the fundamental difference in instrumentation between Flame Emission and Atomic Absorption Spectrometers?
  5. What is optical activity? Give an example.
  6. Compare the energy of the following electromagnetic radiation

(i) Radio wave                 (ii) Infrared rays     (iii) Visible light

  1. Mention the nuclear spin quantum number (I) for 6C12, 1H1
  2. Compare the absorption frequencies of C-C and C=C.
  3. Define ‘base peak’.
  4. What kind of electromagnetic radiation is used to study crystal structure?

 

Part-B   ANSWER ANY FIVE QUESTIONS (5 ´ 8 = 40)

  1. (a) State Beer-Lambert’s law and explain under what conditions it is not applicable.

(b) The molar absorptivity of a particular solute is 2.1 x 104 L cm-1mol-1. Calculate the transmittance through a cuvette with a 5 cm light path for

a 2.0 x 10-6 M solution.

  1. (a) Explain the significance of λmax and ε values in UV-Visible spectroscopy with a suitable example.

(b) Spectrophotometry is a very useful quantitative technique in the applications of biological systems. Can you substantiate this statement with two examples?

  1. Discuss in detail the instrumentation and application of nephelometry.
  2. Explain briefly the principle of ICP AES and its advantages over AAS methods?
    1. Determine the force constant for the C-H bond, given the stretching frequency of the C-H bond as 3000cm-1.

 

  1. Calculate the pH of the following solutions.
  • 10-2 M Ca(OH)2
  • Mixture containing 10-2 M NH4Cl and 10-1 M NH4 Kb of NH4OH is 10-5.
  1. Discuss the applications of isotopic dilution analysis.
  2. Draw the low resolution NMR spectrum of ethyl alcohol and explain.

 

Part-C   ANSWER ANY TWO QUESTIONS (2 ´20 = 40)

 

  1. (a) Define Beer-Lambert’s law explaining the terms involved and state under what conditions it is not applicable.

(b) With a schematic diagram explain the different parts and working of a Double-Beam Spectrophotometer. What are its advantages over a single-beam instrument?                                                                   (10+10)

  1. (a) Discuss the principle and working of an Atomic Absorption Spectrometer and how it can be used in the quantitative determination of lead (Pb2+) in blood.

(b) Give an account of how AAS can be used in studying the toxicological effects of mercury.                                                           (15+5)

  1. (a) Describe the method of determining the pH of a solution using a potentiometer.

(b) Discuss the instrumentation of Gas Chromatography.

  1. (a) Discuss the principle involved in NMR spectroscopy and explain its instrumentation.

(b) Distinguish the following

(i)  CH3   CHCl  CH3      and          CH3  – CH2 -CH2Cl     by NMR

(ii)   CH3  CH2 CHO      and          CH3  -CO -CH3             by IR

(iii)   CH3OH                 and          CH3  CH2 OH             by mass spectrum.

 

 

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Loyola College M.Sc. Chemistry April 2006 Heterocyclics & Natural Products Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 42

FOURTH SEMESTER – APRIL 2006

                                 CH 4954 – HETEROCYCLICS AND NATURAL PRODUCTS

(Also equivalent to CH 4951)

 

 

Date & Time : 25-04-2006/9.00-12.00         Dept. No.                                                       Max. : 100 Marks

 

 

Part- A

   Answer ALL questions.                    (10 ´ 2 = 20 marks)

  1. How is isoquinoline synthesized?
  2. Write the retrosynthesis of pyrimidine.
  3. How is luciferin synthesized? What is its function?
  4. How is the configuration of steroid nucleus defined? How does it affect the stability of nucleus?
  5. During the synthesis of cholesterol, how is the B ring introduced?
  6. What happens when quinoline is subjected to Hofmann’s exhaustive methylation method?
  7. ‘Nametskin rearrangement plays a key role in the biological conversion of Terpenes”. Explain.
  8. How would you convert acetophenone into tropic acid?
  9. Convert: Carvone into Cadelene.
  10. How are terpenes classified? Give an example for each.

Part – B

          Answer any EIGHT questions.             (8 ´ 5 = 40 marks)

  1. How do pericyclic reactions help in the synthesis of heterocyclic compounds? Mention any two examples.
  2. Predict the products in the following reactions.

 

 

  1. Write a note on the electrophilic substitution reactions in thiazole with suitable example.
  2. Explain Traube’s synthesis of uric acid.
  3. How is oestriol synthesized from (±)-oestrone?
  4. Describe any two ring closing reactions during synthesis of cholesterol.
  5. Establish the structure of peepuloidin by synthesis.
  6. How would you establish the structure of veratric acid?
  7. Establish the structure of abietic acid by synthesis.
  8. Give the structure of cocaine. How would you establish and confirm the structure of cocaine by synthesis?
  9. How would you confirm the structure of papaverine by synthesis?
  10. Establish the structure of camphoric acid.

 

Part-C

          Answer any FOUR questions.              (4 ´ 10 = 40 marks)

23     a) What happens when chromone is treated with hydrazine? Write the mechanism of the reaction.

  1. b) Heterocyclic compounds are highly reactive than the corresponding homocyclic compounds. Give suitable explanation with examples.

24     a) Draw the resosnance structures of the following

  1. i) isoquinoline              ii) pyridine                   iii) purine
  2. b) How are the following heterocyclic compounds useful biologically
  3. i) coumarin                  ii) flavone
  4. c) What is Cornforth rearrangement?

25     a) How is the following conversion effected during the synthesis of cortisone?

 

  1. b) What is the biological importance of steroids? Give any two examples.
  2. a) Establish the structure of vitamin-A.
  3. b) What are the functional groups present in heptaphylline? How would you confirm its structure?
  4. a) Establish the structure of gibberelic acid.
  5. b) How would you establish the structure of atropine by synthesis?
  6. How would you convert the following:
  • Tropine into 2-ethylpyridine
  • 1,4-butanedial into ecgonine
  • Camphoric acid into camphor
  • 2,5-dimethoxytetrahydrofuran into tropinone.

 

 

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Loyola College M.Sc. Chemistry April 2006 Electrochemistry Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 40

FOURTH SEMESTER – APRIL 2006

                                               CH 4805/CH 4803 – ELECTROCHEMISTRY

 

 

Date & Time : 20-04-2006/FORENOON     Dept. No.                                                       Max. : 100 Marks

 

 

 

Part–A (20 Marks)

 

Answer ALL questions (10 x 2 = 20)

  1. Calculate the thickness of ionic atmosphere in 0.1M aqueous lanthanum sulphate.
  2. Compare the ion-solvent interaction of the following
    1. 1M aq KCl
    2. 1M aq Al2(SO4)3
  3. λ H+ is the highest among cations in aqueous solution. Why?
  4. How is the capacitance related to the thickness of double layer in Helmholtz Perrin

model?

  1. What are surfactants? Give example.
  2. What do you mean by a polarisable electrode? State the condition for its ideal

polarisability.

  1. What is reaction resistance? Calculate its value of an electrode having equilibrium

current density  2 .08 μA cm.

  1. Nernst equation is a special case of Butler-Volmer equation.Explain.
  2. Determine whether Cu form 0.01 M Cu2+ will be deposited or not.

( SRP :  Cu2+/ Cu = 0.34V )

  1. Obtain the relation between rate and current density of an electro-chemical reaction

from Faraday’s laws.

Part-B (40 Marks)

 

Answer any EIGHT questions (8 x 5 = 40)

  1. 11. What are electro capillary curves? What is its importance?
  2. Derive an expression for the interfacial tension applying parallel plate condenser

model.

  1. Apply Born’s model to find out the energy of ion solvent interaction.
  2. 14. Discuss the evidences for the existence of ionic atmosphere.
  3. 15. The measured emf for the cell Ag, AgBr,KBr || Hg2Br2 | Hg are 0.06839V at 25ºC

and 0.07048V at 30ºC. Write the reaction involved and calculate ∆H, ∆G and ∆S

for the reaction at 25ºC

  1. A 0.2m lead nitrate solution freezes at -0.10ºC. Calculate the dissociation constant

if Kf of water is 1.86 K molal-1

  1. Derive the Butler-Volmer equation for a one electron electrode process.
  2. 18. Define transfer coefficient. How is it determined experimentally?
  3. 19. The reversible potential and c.d of an electrode are 0.22 V and 7.2×10 -4 A cm-2

        respectively. Calculate the c.d across it   at 0.74 V if it has 40% cathodic tendency.

 

  1. 20. The tafel anodic and cathodic slopes of “applied potential vs logi ” of an

electrode process were found to be 0.04 & 0.12 respectively.  Calculate the

ransfer coefficients.

 

  1. 21. Explain the applications of Tafel equations.

 

  1. 22. The exchange current density of Pt/Fe, Feis 2.5 mA cm. Calculate the

current density across the electrode at 25C maintained at 1V when [Fe] = 0.1

M and [Fe]= 0.2 M (SRP = 0.77IV, β = 0.58)

 

Part-C (40 Marks)

 

Answer any FOUR questions (4 x 10 = 40)

 

  1. 23. Discuss sterns model of double layer structure.
  2. 24. Describe ‘Electrokinetic Phenomena’.
  3. 25. Derive Debye Huckel limiting law. How is it verified?
  4. 26. For the system Pt /Fe3+, Fe2+ at 298K the i were measured as shown below:

(mV):             50       80      100     120        150     200

(mA cm)   :  8.01  16.1    25.17    41         82.4   264

Evaluate  io and β

  1. 27. Consider the following mechanism for the deposition iron.

 

Fe2+ + H2O           FeOH+ + H+   eq const K1 ……. (1)

 

                                   FeOH+ + e            FeOH             eq const K2 ……. (2)

 

FeOH + H+ + e          Fe + H2O    eq const K3   ……. (3)

 

Derive the expression for rate if step-2 is rds

  1. Discussion of Butler -Volmer equation for different values of over potentials.

 

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Loyola College M.Sc. Chemistry April 2006 Analytical Chemistry-III Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

THIRD SEMESTER – APRIL 2006

                                                 CH 3805 – ANALYTICAL CHEMISTRY – III

 

 

Date & Time : 18-04-2006/AFTERNOON   Dept. No.                                                       Max. : 100 Marks

Part–A (20 Marks)

Answer ALL questions (10 x 2 = 20)

  1. How large a sample to be taken for analysis using a chemical balance so that the maximum relative uncertainty in the sample weight is 5 ppm?
  2. Explain replacement titration with an example.
  3. Compute the equivalent point potential for titration of
    A2+ vs B4+ (SRP: B4+ / B2+ = 1.44 V ;  A4+ / A2+ = 0.15V )
  4. How is an indicator chosen for a red ox titration?
  5.  Calculate the equilibrium constant for the following reaction:

HCN + OH–   ⇌  CN– + H2O; Ka (HCN) = 1 x 10 -10

  1. How does coulometer differ from potentiometric technique?
  2. Explain how the addition of nitrate ion avoids the liberation of hydrogen?
  3. State an expression for the residual current and explain the terms in it.
  4. Explain the effect of added CN–  on the electrode deposition of Ag.
  5. Mention any two applications of DTA.

 

Part–B (40 Marks)

 

Answer any EIGHT questions (8 x 5 = 40)

  1. Show that the equivalence point for the titration of Fe2+ vs MnO4– is pH dependant.
  2. Explain diverse ion effect
  3. Draw  the titration curves for the follwing:
  • 20 mL of 0.1 M NaOH vs 0.1M CH3COOH
  • 20 mL of 0.1 M NaOH vs 0.1M H2SO4.
  1. Write a note on homogeneous precipitation.
  2. Exactly 0.3525 g of 96.5% Na2SO4 required 37.7 mL of a solution of BaCl2. Calculate the concentration and express the concentration of BaCl2 in scientific notation.
  3. The values of Ka1, Ka2, Ka3 & Ka4 for EDTA (H4Y) are 1x 10-2 , 1x 10-3 , 1x 10-8  & 1x 10-12 ,  respectively. Calculate the conditional stability constant for the following process in 1x 10-2 M HCl.

Fe3+ + Y4-     ⇌       FeY–     ; Kobs = 1 x 1025

    1. How will you estimate Cu2+ by electro gravimetric method?

 

  1. Draw a typical polarogram and indicate the following on the diagram.
  1. Residual current.
  2. Limiting current
  3. Diffusion current
  4. How are they related to each other?
  1. A certain Pb2+ solution gives id = 1.00 mA . To 10 ml of the solution 0.5 ml of 0.04 M of Pb2+ was added. The id of the solution was found to be 1.5 mA. Calculate the concentration of Pb2+ in the unknown solution.
  2. Draw and explain the ampereometric titration curves for the following titrations if the applied potential is maintained at half wave potential of Pb2+
  1. Pb2+ vs CrO42- b . CrO42- vs Pb2+
  1. Explain how the cyclic voltometric technique can be used to determine the electrochemical reversibility and stability of a red-ox  system.
  2. Explain the following with an example.

(i) Fluorimetric estimation of metal ions

(ii) Chemiluminescence

 

Part-C (40 Marks)

 

Answer any FOUR questions (4 x 10 = 40)

  1. The following are peak areas for chromatogram of standard solutions of methyl vinyl ketone (MVK)
Conc. MVK

mmol-1

 Relative peak Area
0.500 3.76
1.50 9.16
2.50 15.03
3.50 20.42
4.50 25.33
5.50 31.97

Apply method of last squares to determine the Conc. of MVK in a sample which yielded relative peak area 6.3, which is the mean of 4 measurements. Also calculate the standard deviation of the result.

  1. Give a critical account of acid-base titration in non-aqueous solvents.
  2. a) Determine the concentration of Fe2+, Fe3+, Ce4+ and Ce3+ in the mixture containing 20.00mL of 0.1000M Ce4+ and 40.00ml of 0.0500M Ce2+ in acidic medium.

(Eº Fe3+/Fe2+ = 0.8V, EºCe4+/ Ce3+ =1.4V)

  1. b) Discuss the factors which influence ∆Pm at the equivalence point.
  1. a) Explain the components of spectro flurometer with a neat diagram.
  1. b) What is hollow cathode? How does it work?
  1. a) Bring out the difference between TG and DTA.
  1. b) How will you prove the liberation of CO in a thermal analysis?
  1. A metal carbonate, MCO3.4H2O (at.wt of metal = 74) on thermal analysis becomes  dihydrate at  160˚C , monohydrate at 200˚C , anhydrous at 260˚C and MO at 550˚C Construct a TG, using graph sheet if 0.725 mg of the salt hydrate is heated from 40˚C to 750˚C.

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Loyola College M.Sc. Chemistry April 2006 Chemistry Of Main Group Elements Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 30

SECOND SEMESTER – APRIL 2006

                                     CH 2809 – CHEMISTRY OF MAIN GROUP ELEMENTS

 

 

Date & Time : 21-04-2006/FORENOON     Dept. No.                                                       Max. : 100 Marks

Part-A

Answer all questions. Each question carries two marks

  1. Both Li and Mg can be used to remove N2 from other gases. Rationalize.
  2. What are electrides? Cite an example.
  3. Europium is frequently found in nature in group II minerals. Comment.
  4. Compounds of alkaline earth metal ions are colorless, but [Be(bpy)(C2H5)2] is bright red in color. Account for this observation.
  5. What are pyrazaboles? Cite an example.
  6. Cite the cyclohexane chair conformational analogue of phosphinoborane.
  7. What are silanes? How do they act as a strong reducing agents for halogens?
  8. What is ZSM-5 catalyst? Mention any two applications.
  9. What is the basic unit of silica present in pyroxene mineral? Draw its structure.
  10. Mention the general trend observed in the hydrolysis of interhalogen compounds.

Part-B

Answer eight questions. Each question carries five marks

  1. Explain the structure of B5H9 using PSEPT theory.
  2. Give an account of the preparation, properties, and structure of C2B10H12.
  3. Write brief notes on (a) silylamines and (b) inorganic rubber.
  4. Explain the role of zeolites as molecular sieves.

15a.  Explain the principle involved in the qualitative estimation of CO by using I2O5.

  1. Complete the following reactions: I2O5 + H2S  ?; I2O5 + HCl  ?

I2O5 + F2BF3   ?

  1. Explain the synthesis of linear phosphazenes and their reactivity toward amines, alkoxides, aryloxides, and organometallic reagents.
  2. Give an account of hexagonal and cubic boron nitrides and their analogy toward graphite and diamond.
  3. Give a brief account of natutrally occurring azamacrocycles.
  4. Explain the chlorinating and oxidising reactions of any two oxides of chlorine.
  5. Give an account of the chemistry of phosphorus compounds with P-P double bonds.
  6. Give an account of the synthesis of aluminium alkyls and their synthetic importance. Comment upon the structures of aluminium alkyls and aluminium aryls.
  7. How is phosphorus sulfides prepared? Depict their cyclic structures.

Part-C

Answer four  questions. Each question carries ten marks

  1. Discuss the bonding in boranes. How can this be extended to cover higher boranes?

24a.  Explain the polyhedral rearrangements of closo-carboranes.                             (5)

  1. Explain the preparation, properties, and structure of borazine.                         (5)

25a.  Give a brief account of the chemistry of oxohalogen fluorides.                       (7)

  1. Write a note on heteropoly blues.                                                                      (3)

26a.  Explain the special equipments and fundamental techniques employed

in the synthesis of main group nonmetal compounds.                                       (6)

  1. Explain the use of hexamethyldisilazane as a silylating agent for organic and inorganic compounds with examples. (4)

27a.  Give an account of naturally occurring ionophores and their interaction with the alkali and alkaline earth metal ions.                                                                    (6)

  1. Explain the mechanism of ion transport across  cell membranes.                      (4)

28a.  Explain the synthesis, reactivity, and structural aspects of rings and cages involving

Si-Si multiple bonding.                                                                                      (6)

  1. Give an account of heterocyclic inorganic ring systems involving Si-O and N-S bondings.                                                                                                       (4)

 

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Loyola College M.Sc. Chemistry April 2006 Analytical Chemistry Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 26

FIRST SEMESTER – APRIL 2006

                                                    CH 1809 – ANALYTICAL CHEMISTRY

 

 

Date & Time : 25-04-2006/1.00-4.00 P.M.   Dept. No.                                                       Max. : 100 Marks

 

 

PART – A

Answer ALL the questions.                                                              (10 ´ 2 = 20)

  1. Triethylamine is a good titrant for the estimation of Cu2+ but not ammonia. Why?
  2. In what way is HPLC is different from GC?
  3. Define confidence interval.
  4. How is the indicator chosen for redox titration?
  5. 00 ml of well water is found to contain10-3 moles of ca2+. Express the concentration of Ca2+ in well water in ppm.
  6. Mention two applications of differential thermal analysis (DTA).
  7. What are the three electrodes used in cyclic voltametric experiment?
  8. What is the significance of molar absorption coefficient?
  9. What is hollow cathode lamp? Where is it used?
  10. Suggest a method for the determination of (a) quinine (b) Na+ (c) Fe3+ in a tap water.

PART – B

Answer any EIGHT questions only.                                                         (8 ´ 5 = 40)

  1. What is thermogram? Explain with an example.
  2. Show that the fraction of completely ionized form of EDTA is a measure of pH.
  3. A 50.00 ml of aliquot of a water sample containing Fe3+ required 13.75 ml of

1.2X10-2 M EDTA when titrated at pH 2.0. Express scientifically the             concentration of Fe3+ in water sample in ppm.

  1. 6000g sample consisting of only CaC2O4 and MgC2O4 is heated at 500 ֯C converting the salts to CaCO3 and MgCO3. The sample then weighs 0.4650g. If the sample had been heated at 900 ⁰C, where the products are CaO and MgO, what would be the mixture of oxides have weighed?
  2. Find out the pH of the following solutions:
    1. Mixture of 20.00 ml of 0.0250 M acetic acid and 40.00 ml of 0.01250 M of sodium hydroxide. Ka of acetic acid is 10-5.
    2. Mixture containing 20.00 ml of 0.0250 M sodium hydroxide and 20.00 ml of 0.0300 M HCOOH. Ka of HCOOH is 10-2.
  3. How will you proceed to collect authentic results for research?
  4. How is sulphate determined by turbidimetric method?
  5. How is Ni2+ estimated by spectrophotocoloriometric method?
  6. How is florescence method more useful than the absorption method in some cases?
  7. Write a note on anodic stripping voltammetry.
  8. Write a note on deviations from Lambert-Beers law.
  9. How is potassium estimated by flame photometric method?

 

PART – C

Answer any FOUR questions only.                                                     (4 ´ 10  = 40)

  1. Discuss the principle and instrumentation of Gas Chromatography.
  2. The sulphate concentration I natural water can be determined by measuring the turbidity that results when excess BaCl2 is added to a measured quantity of the sample. A turbidimeter was calibrated with a series of standard sodium sulphate solutions. The following data were obtained in the calibration.

mg/L                           Reading

0.0                               0.06

0.5                               1.48

  • 28
  • 98

20.0                             4.61

Assuming a linear relationship, derive the equation for the best straight line though these points. Assuming the turbidimeter reading 3.67 for the unknown sample which is the mean of 3 readings, calculate the standard deviation of the result and the concentration of sulphate in the sample.

  1. Discuss the applications of Thermogravimetry. (6)
  2. Explain how the concentration of analyte and products are estimated at the equivalence point in redox titration.
  3. How is thermogravimetry recorded? Mention the factors that affect the thermo gravimetric curves.
  4. Describe the estimation of copper by electrogravimetric method.
  5. Describe the principle and instrumentation involved in atomic absorption method. How is Ca2+ in ppm levels estimated by this method?

 

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Loyola College M.Sc. Chemistry April 2006 Advanced Coodination Chemistry Question Paper PDF Download

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             LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

LM 44

FOURTH SEMESTER – APRIL 2006

                                     CH 4953 – ADVANCED COORDINATION CHEMISTRY

(Also equivalent to CH 4950)

 

 

Date & Time : 25-04-2006/9.00-12.00         Dept. No.                                                       Max. : 100 Marks

 

 

Part-A

Answer all questions. Each question carries two marks

  1. Organometallic compounds of transition metals are invariably colorless. Give reason.
  2. Cl-occupies the lower end of the spectrochemical series, yet the Do value of [RuCl6]3- is comparable to that of [Ru(H2O)6]2+. Offer a reasonable explanation.
  3. How is low-spin and high-spin complexes of d5 metal ion differentiated by electronic spectroscopy?
  4. Mention the causes of tetragonal distortion in transition metal complexes. How is it inferred from epr spectroscopy?
  5. How is the covalent character in transition metal complexes quantified?
  6. What is the oxidation state and spin state of iron centers in Fe_S proteins?
  7. How is p-acceptor series constructed?
  8. What is zero field splitting? Mention its causes in transition metal complexes.
  9. How does angular overlap of metal and ligand aos alter the magnitude of es- and ep-parameters?
  10. Illustrate transmetallation reaction with an example.

Part-B

Answer eight questions. Each question carries five marks

  1. Explain the structural features and biological roles of Fe-S proteins.

12     What is crystal field splitting parameter Dt? How is it manifested when Dqxy > Dqz and Dqxy < Dqz?

  1. How is nitro- and nitrito complexes differentiated by IR spectroscopy?

14     Explain the features of Tanabe-Sugano diagrams. In these diagrams the lowest energy excited state for a high-spin metal ion in a given geometry becomes the ground state for the low-spin state. Explain.

15     What is nitrogen fixation. Explain its mechanism

16     What are coupled chemical reactions? How are they classified? How do you infer  such a process from cyclic voltammetry?

  1. Explain the structural aspects and biological roles of cytochromes.
  2. Give an account of the structural features of biological electron transfer agents.
  3. What is chelation therapy? Mention the specific disease which is cured by this therapy.

20     Explain the principle of AC polarography. How is the reversibility of a redox couple evaluated by this technique?

  1. What are optically trasparent thin layer electrodes? Mention their importance.
  2. What is static dynamic Jahn Teller distortion? How is it studied by esr spectroscopy?

Part-C

Answer four questions. Each question carries ten marks

23a   Explain the electronic spectral features of low-spin and high-spin Oh complexes of d6 metal ion.                                                                         (4)

b     Explain the electronic spectral features of tetragonally distorted Oh complex of low-spin d6   metal   ion and the method of evaluating the crystal field parameters. (6)

24a.  Derive Marcus-Hush equation to compute the rate constant of electron transfer reactions. (7)

  1. How do you differentiate inner- and outer-sphere electron transfer reactions?            (3)

25a.  Explain hyperfine and superhyperfine splittings.                                                (3)

  1. The epr spectrum of a high spin Mn(II) complex, doped onto a diamagnetic host, consists of 30 epr lines when there is no hyperfine splitting by the ligand. Interpret the spectrum with the help of a qualitative hyperfine splitting diagram. (7)

26a.  p-Donation by ligands lowers 10Dq values whereas p-back bonding increases 10Dq values and facilitates M-L bonding. Explain with the help of MO theory with qualitative MO energy level diagrams.                                           (5)

  1. Account for the difference in the properties of metal carbonyls and complexes of nitrogen donor ligands in the light of MO theory.                                        (5)

27a.  Explain the principles of angular overlap model.

  1. Show that  Dt =  4/9Do with the help of this model.

28a.  Illustate coordination template effect with examples.                                      (4)

  1. What are compartmental ligands? Explain the method of synthesizing dinuclear macrocyclic and macroacyclic compartmental ligands with illustrative examples.(6)

 

 

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Loyola College M.Sc. Chemistry Nov 2006 Quantum Chemistry Question Paper PDF Download

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                     LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034    M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 11

FIRST SEMESTER – NOV 2006

         CH 1800 – QUANTUM CHEMISTRY

 

 

 

Date & Time : 26-10-2006/1.00-4.00          Dept. No.                                                              Max. : 100 Marks

 

 

 

Part-A   ANSWER ALL QUESTIONS (10 x 2 = 20)

 

  1. Explain the Ultraviolet catastrophe.
  2. The size of an atomic nucleus is 10-14 Calculate the uncertainty in momentum of the electron if it were to exist inside the nucleus.
  3. The accepted wave function Φ for a rigid rotor is Nexp(±imφ) for 0≤φ≤2π.

Determine N.

  1. Show that the function Ψ(x,y,z) = cosax cosby coscz (where a,b,c are constants) is an

eigen function of the Laplacian Operaator ∇2. What is its eigen value?

  1. Show that the energy E = 14h2/8ma2 of a particle in a cubic box of side ‘a’ is triply degenerate.
  2. What is a well-behaved or acceptable wave function in quantum mechanics?
  3. Explain the radial plot and the radial probability density plot for 2s electron.
  4. What is Born-Oppenheimer approximation?
  5. Write the Hamiltonian operator for the H2+ molecular ion in atomic units defining

each term  involved in it.

  1. Write the Slater determinant for the ground state of He atom which takes into account the antisymmetric condition of Pauli Exclusion Principle for electrons.

 

 

Part-B   ANSWER ANY EIGHT QUESTIONS (8 x 5 = 40)

 

 

  1. Discuss the failures of classical mechanics and the success of quantum theory in the explanation of black body radiation. .
  2. What are quantum mechanical postulates? Explain briefly any two of the postulates.
  3. The work function for Cesium is 2.14 eV. What is the kinetic energy and the speed of the electrons emitted when the metal is irradiated with the light of 300 nm?
  4. What is a hermitian operator? Show that the eigen value of a hermitian operator is real.                                                                                                                 (2+3)
  5. The normalized wave function for the 1s orbital of Hydrogen atom is

ψ = (1/√π)(1/a0)3/2exp(-r/a0). Show that the most probable distance of the electron is    a0.

  1. Explain Bohr’s correspondence principle with a suitable example.
  2. Write the Schroedinger equation for 1-D harmonic oscillator. Verify ψ = (2a/π)1/4exp (-ax2) is an eigenfunction of the Hamiltonian operator for the 1-D harmonic oscillator.

 

 

  1. What is a node? Draw the first three wave functions and probability plots for the Particle in a 1-D box and Simple Harmonic Oscillator models and compare them.

(1+4)

 

 

 

  1. The spacing between adjacent rotational lines in the spectrum of HCl molecule is

6.33 x 1011s-1. Calculate the moment of inertia of HCl molecule and the internuclear spacing  if the atomic masses are H = 1.008 and Cl = 34.97.

  1. (a) Explain the conditions under which an electron may give a continuous or a discrete spectrum.
    • The continuous probability distribution Gaussian function is given by

f(x) = Aexp(-x2/2a2) with interval (-∞, +∞). Show that <x> = 0.                (2+3)

  1. In solving the H2+ problem using the LCAO method, the lowest energy obtained is given by E+ = (HAA + HAB) / (1+SAB) where A and B refer to the two hydrogen nuclei. Explain each of the integrals in the above equation and their significance.
  2. With a suitable example explain the quantum mechanical tunneling.

 

 

Part-C   ANSWER ANY FOUR QUESTIONS (4 x 10 = 40)

 

  1. (a) Write the Schroedinger equation to be solved for H atom and solve it for its energy using a simple solution, which assumes the wave function to depend only on the distance r and not on the angles θ and φ

(b) In the Compton experiment, a beam of x-rays with wave length 0.0558 nm is scattered through an angle of 45˚. What is the wavelength of the scattered beam?

(7+ 3)

  1. (a) Apply the variation method to get an upper bound to the ground state energy of hydrogen atom using the trial function φ(r) = exp(-αr2). Compare your result with the true value.

(b) Discuss the Pauli Principle of antisymmetric wave function.             (6+4)

  1. Set up the Schroedinger equation for a rigid rotor in polar coordinates and solve it for its energy and wave function.

26  (a) Set up and solve the Schroedinger wave equation for a 1-D particle in a box model for its energy and wave function.

(b) For the hexatriene molecule, calculate λmax on the basis of particle in a one dimensional box of length equal to 7.3Ǻ                                                     (7+3)

  1. Discuss the Molecular Orbital treatment of H2 molecule and explain how the Valence

Bond (Heitler-London) method overcomes some of the difficulties of MO theory.

  1. (a) What are the three important approximations of Huckel-LCAO-MO theory?

(b) Using this theory set up the secular equation and secular determinants for

allyl radical and hence obtain its energy levels.                                            (3+7)

 

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Loyola College M.Sc. Chemistry Nov 2006 Quantum Chemistry & Group Theory Question Paper PDF Download

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                     LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034    M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 16

FIRST SEMESTER – NOV 2006

CH 1808 – QUANTUM CHEMISTRY & GROUP THEORY

 

 

 

Date & Time : 26-10-2006/1.00-4.00               Dept. No.                                                              Max. : 100 Marks

 

 

 

 

 

Part-A   ANSWER ALL QUESTIONS (10 x 2 = 20)

 

  1. Show that Ae-ax is an eigen function of the operator d2/dx2. What is the eigen value?
  2. Define an orthonormal function.
  3. The energy of a particle moving in a cubic box of side ‘a’ is 3h2/2ma2. What is its degeneracy?
  4. What is a node? Draw the radial distribution plot for 3s orbital of H-atom and indicate where the nodes are.
  5. What is the value of [x,px]? What is its physical significance?
  1. What is a fermion? Give an example.
  2. Set up the Schroedinger wave equation to be solved for the rigid rotor in spherical

polar coordinates.

  1. Define the Variation Principle and mention its significance.
  2. Identify the point groups for the following molecules:

(a) POCl3         (b) SF6   (c) Br2            (d) Ni(CN)42- (square planar)

  1. The following irreducible representations are parts of the C4v and C2h character

tables. What do x and y in these tables mean and in what way they differ from

each other?

 

C4v    E    2C4    C2     2σv   2σd                   C2h           E     C2           i      σh

 

 

E      2      0    -2     0     0       (x, y)       Bu         1     -1      -1        1        x,y

 

 

Part-B   ANSWER ANY EIGHT QUESTIONS (8 x 5 = 40)

 

11 Apply variation theorem to the problem of particle in a 1-D box of length a, by taking

ψ = x(a-x) as a trial function for 0≤x≤a.

 

  1. What is a hermitian operator? What is its significance in quantum mechanics?

Show that the eigen value of a hermitian operator is real

 

  1. Show that the wave functions describing 1s and 2s electron for He atom are

orthogonal to each other, given Ψ1s = (1/4π)1/2 2(2/a0)3/2 exp(-2r/a0)   and

Ψ2s = (1/4π)1/2 (1/a0)3/2 (2 – 2r/a0) exp (-r/a0).

 

  1. What is a Slater determinant? Write the four Slater determinants for the excited state

of He atom (1s,2s)

 

 

 

 

  1. The force constant of 79Br is 240 Nm-1. Calculate the fundamental vibrational

frequency and the zero-point energy of the molecule.

 

 

  1. Explain briefly with a suitable example:

(a) Bohr’s correspondence principle (b) Born –Oppenheimer approximation.      (3+2)

 

  1. The wave function of 1s orbital of Li2+ is given by Ψ1s = (1/√π) (Z/a0)3/2 exp(-Zr/a0),

where a0 is the most probable distance of the electron from the nucleus. Show that the

average distance is a0/2.  [Help:  0ò¥ xn e-qx dx = n! / qn+1]

 

  1. (a) Show that [x, d/dx] = -1

(b) What are the values of [x,px] and [L2,Lx]? What is their physical significance?

(2+2+1)

 

  1. Write the Schroedinger equation to be solved for H atom and solve it for its

energy using a simple solution, which assumes the wave function to depend only

on the distance r and not on the angles θ and φ.

 

  1. Explain the following with a suitable example:

(a) A ‘Class’ in group theory (b) Principle of mutual exclusion                  (3+2)

 

  1. Explain ‘quantum mechanical tunneling’ with a suitable example.

 

  1. Find the number, symmetry species of the infrared and Raman active vibrations of

CCl4, which belongs to Td point group by reducing the following reducible

representation. State how many of them are coincident.

Td          E       8C3            3C2             6S4            6σd

GCCl4         15        0              -1                 -1             3

 

Td         E          8C3      3C2      6S4       6σd

A1        1          1          1          1          1                             x2+y2+z2

A2        1          1          1          -1         -1

E          2        -1           2          0          0                            (2z2-x2-y2, x2-y2)

T1         3          0          -1         1          -1         (Rx,Ry,Rz)

T2         3          0          -1         -1         1         (x,y,z)         (xy,xz,yz)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Part-C   ANSWER ANY FOUR  QUESTIONS (4 x 10 = 40)

 

  1. (a) Derive the wave function and energy for the particle in a 1-D box.

(b) A cubic box of 10Å on the side contains 8 electrons. Applying the simple particle in a box model, calculate the value of ΔE for the first excited state of this system.

 

  1. (a) What are the three important approximations of Huckel-LCAO-MO theory?

(b) Using this theory set up the secular equation and secular determinant for

ethylene and hence obtain its energy levels and corresponding wave functions.

 

  1. What is a permutation operator? State and illustrate the Pauli Exclusion Principle for

the ground state of He atom that wave functions must be antisymmetric in the

interchange of any two electrons.

 

  1. (a) Derive the time-independent Schroedinger equation from the time-dependent

equation and show that the property such as electron density is time independent

although the wave function describing an electron is time dependent.

(b) The microwave spectrum of the CN radical shows a series of lines spaced by a

nearly constant amount of 3.798 cm-1. What is the bond length of CN?        (6+4)

 

  1. (a) In solving the H2+ problem using the LCAO method, the lowest energy obtained is

given by E+ = (HAA + HAB) / (1+SAB) where A and B refer to the two hydrogen

nuclei. Explain each of the integrals in the above equation and their significance

(b) Outline the salient features of VB (Heitler-London) theory as applied to H2

                 molecule                                                                                                         (5+5)

 

  1. The MoO4 belongs to the Td point group. Find the reducible representation for the

molecule using the four Mo – O bonds as bases and reduce this into irreducible

representation using the Td character table given below and show that the bonds in

MoO4 are more likely to be sd3 hybrids.

 

Td          E          8C3      3C2      6S4       6σd

 

 

A1        1          1          1         1         1                                 x2+y2+z2

A2        1          1          1         -1         -1

E         2          -1         2         0         0                                 (2z2-x2-y2, x2-y2)

T1        3          0          -1         1         -1         (Rx,Ry,Rz)

T2         3          0          -1         -1         1         (x,y,z)              (xy,xz,yz)

 

 

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Loyola College M.Sc. Chemistry Nov 2006 Photochemistry & Organic Synthesis Question Paper PDF Download

by

                            LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 22

THIRD SEMESTER – NOV 2006

         CH 3808 – PHOTOCHEMISTRY AND ORGANIC SYNTHESIS

 

 

Date & Time : 25-10-2006/9.00-12.00   Dept. No.                                                       Max. : 100 Marks

 

 

 

 

Part A

Answer ALL questions.                                                                  (10 ´ 2 = 20 marks)

 

  1. What is benzoin reaction?
  2. Draw the Frontier Molecular Orbital interaction of 1,3-butadiene and ethylene under photochemical conditions.
  3. How will you effect the following isomerisation? Write the mechanism.

 

  1. Write the Woodward Hoffmann rules for electrocyclization reaction.
  2. Explain the change in the geometry of excited state molecule in a photochemical process and the variation in its physical property.
  3. What is Norrish type I and II cleavage reactions? Give suitable examples.
  4. What are the important guidelines to be followed while choosing alternate synthetic route?
  5. Explain the umpolung concept of synthesis with suitable example.
  6. Explain the mechanism of the following reaction.

 

  1. What are the products formed when benzene is subjected to Birch reduction?

 

Part B

Answer any EIGHT questions.                                                     (8 ´ 5 = 40 marks)

 

  1. Explain Michel addition reaction with an example.
  2. Draw correlation diagram for the electrocyclization of 1,3,5-hexatriene for the dis-rotatory approach. State whether the reaction is feasible by thermal or photochemical means.
  3. Predict the products in the following pericyclic reactions and explain the mechanism with proper stereochemistry.

 

 

 

 

 

 

 

 

  1. Predict the mechanism of the following reaction.

 

  1. Explain the mechanism of Paterno Buchii reaction. How does this take place in case of an alkyne?
  2. Explain the mechanism of photochemical rearrangement of 4,4-diphenylcyclo- hexenone.
  3. Describe a general scheme of synthesizing various mono functionalized compounds starting from alcohols.
  4. Describe a suitable method to prepare the following compounds.

 

 

 

  1. What is chemoselectivity? How well are chemoselective reactions performed? Explain with any two examples.
  2. Explain the mechanism of electroorganic synthesis with an example.
  3. How is cubane synthesized? Explain the mechanism.
  4. Explain the mechanism of oxidation using
  5. a) mercuric acetate and b) SeO2.

 

Part C

Answer any FOUR questions.                                                       (4 ´ 10 = 40 marks)

 

  1. a) Explain the mechanism of following reactions.
  2. i) Hydroboration of carbonyls ii) Darzens reaction.
  3. b) Predict the reaction mechanism of the following reaction.

 

 

 

  1. a) Predict the product in the following sigmatropic rearrangement reactions.

 

 

 

  1. b) Explain the effect of substituents on the cycloaddition reactions.

 

 

 

 

 

 

 

 

 

  1. a) Predict the product and explain the mechanism of following reactions.

 

 

 

  1. b) Derive Stern Volmer expression for photochemical quenching.
  2. Explain the complete retrosynthetic analysis and subsequent synthesis of longifolene.
  3. Explain the mechanism of following reactions.
  4. a) Wolf Kishner reduction
  5. b) Claisen-Schmidt reaction
  6. c) Stobbe reaction with aromatic ketones
  7. Explain the retrosynthetic analysis of the following compounds

 

 

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Loyola College M.Sc. Chemistry Nov 2006 Organic Reaction Mechanism & Stereochemistry Question Paper PDF Download

by

                        LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 14

FIRST SEMESTER – NOV 2006

CH 1806 – ORGANIC REACTION MECHANISM & STEREOCHEMISTRY

 

 

Date & Time : 28-10-2006/1.00-4.00     Dept. No.                                                       Max. : 100 Marks

 

 

 

PART A

Answer ALL questions.                                                                   (10 ´ 2 = 20 marks)

 

  1. What is transition state theory? Mention its importance.
  2. What are the various kinetics experiments to study the mechanism of a particular reaction?
  3. Classify the rearrangement reactions and give example for each.
  4. What is memory effect? Explain with an example.
  5. Write a short note on catalytic dehydrogenation.
  6. Explain Cram’s rule with a suitable example.
  7. Explain why meso-stilbene dichloride on heating with pyridine at 200°C gives no product while dl-isomer gives alkene readily.
  8. What is epimerisation? Give an example.
  9. Explain Walden inversion with a suitable example.
  10. Explain the racemization via cations with a suitable example.

 

 

PART B

Answer any EIGHT questions.                                              (8 ´ 5 = 40 marks)

 

  1. How trapping of intermediate, cross-over experiments and isotopic labeling studies help to show that a reaction is intermolecular? Explain with suitable examples. (5)
  2. How does the kinetics study in chain and parallel reactions help to design the reaction mechanism? Explain with suitable examples. (5)
  3. Explain the mechanism of the following rearrangement reactions. (2 ´ 2½)
  4. a) Beckman rearrangement b) Baeyer Villiger rearrangement
  5. a) Why secondary amides do not undergo Hoffmann degradation? Give reasons. (2½)
  6. b) Explain the mechanism of Claisen rearrangement with suitable example. (2½)
  7. Explain the mechanism of NaBH4 reduction. How is it chemoselective? Explain with an example.                                                                                                    (5)
  8. How direct electron transfer can bring in reduction? Explain the mechanism with any two examples.                                                                                                    (5)
  9. Predict the Cotton effect by the sign of the most occupied octant in the following compounds:

(i) (+)-trans-1-methyl-2-decalone            (ii) 5a-cholestan-6-one.   Explain.                  (2 ´ 2½)

  1. Dehydrobromination of diastereoisomeric a-phenyl-b-bromo-b-benzoylpropionic acids with    hot pyridine give different products.  Explain.
  2. Write notes on: a) asymmetric destruction  and  b) asymmetric synthesis
  3. ‘The cotton effect curves of (+)-3-methylcyclopentanone in methanol shows only a 24%                 reaction upon addition of acid’.  Explain.
  4. Give an example for first order and second order asymmetric transformations. Explain.
  5. What are the different methods of resolution of racemic mixture? Explain any two methods.

 

 

PART C

Answer any FOUR questions.                                                          (4 ´ 10 = 40 marks)

 

  1. a) How does the kinetics study help to design the reaction mechanism in the following      reactions?                                                                                                    (2 ´ 2½)
  2. i) Aldol condensation ii) Benzidine rearrangement
  3. b) How stereochemical study and isotopic labeling study help to design a reaction      mechanism as intramolecular? Explain with suitable examples.                                   (5)
  4. a) Explain the mechanism of                                                             (2 ´ 2½)
  5. i) Fischer Indole synthesis and      ii) Favorskii rearrangement
  6. b) Predict the products in the following reactions. Give suitable reasons. (5)

 

  1. a) Explain the reductive coupling of carbonyl compounds with any two examples. (5)
  2. b) How does specific dehydrogenation in steroids take place? Explain the mechanism with an (5)
  3. a) Explain the octant rule with a suitable example.
    b) Predict the Cotton effect by the sign of the most occupied octant in the following     compounds:

(i) 3-bromo-4-methoxycyclohexanone           (ii) 3-methylcyclohexanone

  1. Explain the following:
    a)  trans-4-t-butylcyclohexane carboxylic acid is more stronger than cis-isomer.
    b) erythro-3-bromo-2-butanol with HBr gives meso product
    c) Dehydrochlorination of 1,2-diphenyl-1-chloroethane gives trans product fastly but cis     product slowly.
  2. a) Explain the following with suitable example.
    a)      Asymmetric destruction
    b)      Bredt’s rule
  3. c) Axial haloketone rule
  4. Prelog’s rules

 

 

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Loyola College M.Sc. Chemistry Nov 2006 Organic Chemistry-III Question Paper PDF Download

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                            LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 18

THIRD SEMESTER – NOV 2006

                              CH 3800 – ORGANIC CHEMISTRY – III

 

 

Date & Time : 25-10-2006/9.00-12.00      Dept. No.                                                    Max. : 100 Marks

 

 

 

Part A

Answer ALL questions.                                                                       (10 ´ 2 = 20 marks)

  1. Write a short note on [4+2]-cycloaddition in dipolar compounds.
  2. What is a cheletropic reaction? Give an example.
  3. What is Alder’s endo rule. Explain with an example.
  4. Define the following. a) Photo quenching b) II law of photochemistry
  5. Write a short note on the fate of the excited state molecules in a photochemical reaction.
  6. Explain retro synthetic approach with an example.
  7. What are annelation reactions? Give an example.
  8. How would you plan the synthesis of 3-methyl-6-hepten-2-one by span technique?
  9. Give a synthesis based on umpolung concept of seebach.
  10. What are the importance of three component system in Clemmensen reduction?

 

 

Part B

Answer any EIGHT questions.                                                           (8 ´ 5 = 40 marks)

  1. Draw a correlation diagram for the cycloaddition reaction of 1,3-butadiene and ethylene. State whether the reaction is thermally or photochemically feasible.
  2. Predict the products in the following pericyclic reactions and explain the mechanism with proper stereochemistry.

 

 

  1. Predict the mechanism of the following reaction.

 

  1. Derive Stern Volmer expression for photochemical quenching.
  2. Explain the photochemical rearrangement of 4,4-diphenylcyclohexenone.
  3. What is Barton reaction? Explain its reaction mechanism in a steroidal compound.

 

 

 

17.    Explain the mechanism of Birch reduction. Identify the products obtained when the following are subjected to this reduction: (a) Benzoic acid and (b) Anisole.  Justify your answer.

18.    Explain the importance of electroorganic synthesis over the conventional synthesis in synthesizing bridged compounds with suitable examples.

19.    Explain the synthesis of reserpine.

20.    Explain the mechanism of Reformatsky reaction.  How is this reaction useful in organic synthesis?

21.    Oxymercuration-demercuration reactions follow Markownikov’s addition while Hydroboration-oxidation follows Anti-Markownikov’s addition. Why?  Explain with two suitable examples.

22.    What are stereospecific control elements?  How are they useful in organic  synthesis?

Part C

         Answer any FOUR questions.                                                   (4 ´ 10 = 40 marks)

  1. Predict the reaction mechanism of the following reactions.

a)

 

b)

 

 

  1. a) Predict the products of following reactions.

 

 

  1. b) “Cycloaddition reactions are regioselective.” Explain with any two examples.

 

 

 

 

 

 

 

  1. a) Photo reduction of benzophenone with diphenylmethanol involves a quantum     yield of 1 compared to that of 2-propanol with 2. Explain.
  2. b) Explain the photochemical rearrangement of 4,4-diphenylcyclohexen-2,5-    dienone.
  3. a) How would you synthesise Norethisterone?
  4. b) What are the advantages of selenium dioxide oxidation? Explain the mechanism      with suitable examples.
  5. a) Explain the steps involved in the synthesis of longifoline.
  6. b) Identify the product in the following. Explain with mechanism.
    Me2C=CH-CO-CH3      A   +   B
  7. Explain the following:
  8. Perkin reaction is most widely used in the synthesis of coumarin.
  9. Benzaldehyde is condensed with ketonic ester in retrograde aldol condensation reaction.
  10. Alkylation of active methylene group is an important step in organic synthesis in increasing carbon skeleton.

 

 

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Loyola College M.Sc. Chemistry Nov 2006 Organic Chemistry-I Question Paper PDF Download

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                        LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 12

FIRST SEMESTER – NOV 2006

CH 1801 – ORGANIC CHEMISTRY – I

 

 

Date & Time : 28-10-2006/1.00-4.00 Dept. No.                                                       Max. : 100 Marks

 

 

 

PART – A

Answer all the questions                                                                            (10 × 2 = 20 marks)

 

  1. Explain Prelog’s rule with a suitable example.
  2. In 4-t-butylcyclohexanecarboxylic acid, trans form is more acidic than cis isomer in 66% aquesous DMF.
  3. What is mutarotation? Give an example.
  4. Dehydrobromintion of threo-1-bromo-1,2-diphenylpropane is faster than erythro.
  5. Write the most stable conformation of
    (a) 1,2,2,6,6-pentamethol-4-hydroxy-4-phenylpiperidine
    (b) 1,3-di-t-butylcyclohexane
  6. Arrange the following compounds in the decreasing order of basicity. Justify your answer.

i)methylamine  ii) ethylamine  iii) n-propylamine  iv) iso-propylamine

  1. How does DS‡ factor help in understanding the kinetics of chemical reactions?
  2. Write the mechanism of Chichibabin reaction.
  3. What are consecutive reactions? Apply conditions and derive specific rate expression.
  4. How does trapping method help in determining the mechanism of a chemical reaction?

 

 

PART – B

Answer EIGHT the questions                                                                       (8 × 5 = 40 marks)

 

  1. Dehydrobromination of diastereoisomeric a-phenyl-b-bromo-b-benzolypropionic acids with hot pyridine give different products.
  2. Explain the determination of configuration of (-)mandelic acid and (-)phenylmethylcarbinol with respect to (+)lactic acid.
  3. Acetolysis of  diastereoisomeric   3-phenyl-2-pentyltosylate   and 2-phenyl-3-pentyltosylate give different products.   Account for your answer and explain the formation of the products.
  4. Explain Walden inversion with two suitable examples.
  5. Explain the racemization via cations and anions with suitable examples.
  6. Write notes on: a) asymmetric destruction  and  b) asymmetric synthesis
  7. How do inductive and field effects affect the second substitution in aromatic systems? Explain with suitable examples.
  8. Write the mechanism of following name reactions.
  9. a) Bucherer reaction     b) Fischer-Hepp rearrangement
  10. Account for the following
  11. a) Diazotization of aniline follows third order kinetics.
  12. b) 2,6-Dimethyl-4-nitroaniline is weaker base than 2,5-dimethyl-4-nitroaniline.
  13. Compare the ipso-attack in aromatic electrophilic substitution with the SNAr mechanism.    Explain with an example.
  14. The diazotization of aniline in moderately concentrated acid has been found to be

second order in HNO2. Explain.

 

 

  1. Predict the products in the following reactions.
  2. i)  2,4,5-trimethyliodobenzene  +  NaNH2                  ¾®   ?
  3. ii) 2,6-dimethyl-1,4-dinitrobenzene  +  C2H5O–         ¾®   ?

 

 

PART – C

Answer FOUR the questions                                                                                     (4 × 10 = 40 marks)

 

  1. a) How would you resolve (±)-alcohol mixture by a suitable resolving agent?
  2. b) ‘Mandelic acid is racemized by a base easily but not atrolactic acid’.
  3. a) How do isotopic labeling and stereochemistry help in predicting suitable reaction                  mechanisms? Give examples.
  4. b) How are the following conversions effected?
  5.                i)          benzene                                   ¾®    naphthalene
  6.             ii)         sodium phenylsulphonate       ¾®    sodium phenoxide
  7. a) Prove that Hammett equation is LFER. How is the orientation and reactivity of

electrophiles normally studied? Briefly explain with examples.

  1. b) How do cross over experiments help in determining the mechanism of a chemical

reaction. Explain with an example.

  1. a) Explain the octant rule with a suitable example.
    b) Predict the Cotton effect by the sign of the most occupied octant in the following     compounds:

(i) (+)-trans-1-methyl-2-decalone            (ii) 3-methylcyclohexanone

  1. Explain the following:
    a) meso-stilbene dichloride on heating with pyridine at 200°C gives no product while
    dl-isomer gives alkene readily.
    b) erythro-3-bromo-2-butanol with HBr gives meso product
    c) Dehydrochlorination of 1,2-diphenyl-1-chloroethane gives trans product fastly but cis     product slowly.
  2. Explain the following:
    a) The cotton effect curves of (+)-3-methylcyclopentanone in methanol shows only a 24%     reaction upon addition of acid.
  3. b) meso form of stilbene dichloride has a dipole moment 1.27D while the dl-pair has 2.75D.
    c) Debromination of meso-2,3-dibromobutane by iodide ion is faster than its dl–pair

 

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Loyola College M.Sc. Chemistry Nov 2006 Molecular Spectroscopy Question Paper PDF Download

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                          LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 24

THIRD SEMESTER – NOV 2006

CH 3810 – MOLECULAR SPECTROSCOPY

 

 

Date & Time : 30-10-2006/9.00-12.00      Dept. No.                                                   Max. : 100 Marks

 

 

PART A

Answer ALL the questions.                                                 (10 x 2 = 20 Marks)

  1. Convert 0.15 nm to Hz and state what sort of transition this corresponds to.
  2. What are stokes and anti-stokes lines?
  3. Name two techniques to enhance the sensitivity of the spectral lines.
  4. What is the basic principle of Mossbauer spectroscopy?
  5. From the relative abundance of the (M+2)+ peaks in the mass spectra, can you distinguish chloro compounds from Bromo compounds?
  6. State the principle of PES. What is the essential difference between XPES and UV-PES?
  7. A free electron is placed in a magnetic field of strength 1.3 T. If ge is 2.0023 and βe is 9.274 x 10-24 JT-1. Find the ESR frequency in GHz.
  8. What are the advantages of using TMS as the standard in NMR experiments?
  9. Compare the 1H and 13C NMR spectra in terms of the range of chemical shifts and intensity of the peaks (peak areas)
  10. What is spin-spin relaxation?

PART – B

Answer ANY EIGHT questions                                          (8 x 5 = 40 Marks)

  1. What are the factors that affect the width of the spectral lines? Explain any two of them.
  2. The observed infrared absorption and Raman spectral lines of Chlorate ion (ClO3–) are given below. Predict the structure of Chlorate ion.
Raman Frequencies (cm-1 )                        IR Frequencies (cm-1

450 (depolarized)                                           434 (^)

610 (polarized)                                               624 (||)

940  (depolarized)                                          950 (^)

982 (polarized)                                               994 (||)

 

  1. The frequencies of vibration of the following molecules in their v = 0 states are HCl: 2885 cm-1; D2: 2990 cm-1; DCl: 1990 cm-1 and HD: 3627 cm-1, calculate the energy change in the reaction HCl + D2 à DCl + HD.
  2. The mass spectrum of a compound having the empirical formula C11H12O2, shows the following peaks at m/e : 78,105 (Base peak), 122, 135,176 (Molecular Peak). Identify the compound and account for the fragments.
  3. At what temperature will the number of I2 molecules in the v=1 level be one-tenth of that in the v=0 level? Given = 214.6 cm-1;xe = 0.6 cm-1 and k = 1.38 x 10-23J K-1.
  4. Explain Quadrupole mass spectrometer.
  5. Explain what is Zero Field or Crystal Field Effect in the fine structure of ESR

and the factors that contribute to that.

  1. State and explain Franck-Condon Principle. With diagrams explain the

variations in intensity of electronic spectra explained by this principle?

  1. What is population inversion? Prove that a population inversion cannot

be achieved in a two level system while it is possible in a three level system.

  1. (a) With an example explain Diamagnetic Anisotropy.

(b) The chemical shift of the CH3 protons in diethyl ether is ∂ = 1.16 ppm and that of the CH2 protons is 3.36 ppm. What is the difference in local magnetic fields between the two regions of the molecule when the applied field is 16.5 T?

  1. Predict

(a) the spin-spin splitting pattern for the protons of neopentane molecule

and the peaks’ intensity distribution.

(b) the hyperfine splitting of the ESR spectrum of ۰CD3 and ۰CHD2 radicals.

[note: the spin of D is 1]

  1. Explain the principle of 2D NMR highlighting its advantages.

PART – C

Answer ANY FOUR questions                                            (4 x 10 = 40 Marks)

  1. a) Three consecutive lines in the rotational spectrum of a diatomic molecule are observed at 84.544, 101.355 and 118.112 cm-1.  Assign these lines to their appropriate J’’ àJ’ transitions and deduce the values of B and D.
  2. b) How are meta stable ions produced and how are they useful in identifying the molecular formula of a compound?
  3. a) The fundamental band of HCl is centered at 2886 cm-1.  Assuming that the internuclear distance is 12.76 nm, calculate the wave number of the first two lines of each of the P and R branches of HCl.
  4. b) Explain the pure rotational spectra of symmetric top molecules.
  5. a) Explain the fact that the Mossbauer spectrum of [Fe(CN)5NO]2- gives two lines whereas [Fe(CN)6]4- spectrum gives one line.
  6. b) In the rotational Raman spectrum of HCl, the displacements from the exciting lines are represented by Dn = ± (62.4 + 41.6 J) cm-1.  Calculate the moment of inertia of the HCl molecule.
  7. Explain the following with a suitable example:

(a) spin-spin coupling in 1H-NMR

(b) mechanism of spin-spin coupling for geminal protons

(c) the multiplicity and intensity distribution represented by the ‘coupling tree’

 

  1. (a) Explain briefly: (a) spin-spin relaxation (b) Fourier Transformation Technique.

(b) Sketch the esr spectrum of °CH3 and explain its nuclear hyperfine splitting.

 

  1. (a) What are asymmetry electric field gradient and asymmetry parameter, η? How

are they related? What is the significance of η?

(b) Taking any laser as example explain the three most important components

of a laser?

 

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Loyola College M.Sc. Chemistry Nov 2006 Material Science Question Paper PDF Download

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                        LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – CHEMISTRY

AD 25

THIRD SEMESTER – NOV 2006

CH 3875 – MATERIAL SCIENCE

 

 

Date & Time : 06-11-2006/9.00-12.00   Dept. No.                                                       Max. : 100 Marks

 

 

PART – A

Answer all the questions                                  (10 x 2 = 20)

 

  1. What are “glide planes”?
  2. Give the expression for Brinell Hardness number.
  3. Mention few applications of single crystals.
  4. List the thermodynamical properties that can be measured using TG/DSC methods.
  5. Write a note on “electron charge density maps”.
  6. What is Meissner effect?
  7. What is Hall effect?
  8. What is breakdown diode? What are its uses?
  9. What is Josephson’s effect?
  10. What are ferrites? What is the role of this compound in super conductivity?

 

 

PART – B

 

Answer any eight questions                                 (8 x 5 = 40)

 

  1. Outline the principle, instrumentation and applications of thermogravimetric method.
  2. State Brags’s law. Discuss the powder method of X-ray diffraction.
  3. With neat sketch explain the Bridgman-Stockbarger method of crystal growth from melt.
  4. What are Miller indices? Illustrate their formation in different planes of a cube.
  5. Discuss the role of modulus as an essential parameter in the structural design.
  6. Describe the slow evaporation technique of growing crystals with Manson jar apparatus.
  7. How are cooper pairs formed? Explain BCS theory of superconductivity.
  8. Describe the role of TaS2 in high temperature superconductivity.
  9. Describe domain theory to account for the Hysteresis behaviours of magnetic materials.
  10. Write short notes on a) LED b) Photo voltaic cell.
  11. Explain qualitatively how a p-n junction functions as a rectifier.
  12. Distinguish between Zenner breakdown and avalanche breakdown.

 

 

 

PART – C

 

Answer any four questions                                                 (4 x 10 = 40)

 

  1. Describe (i) Chemical reaction (ii) Chemical reduction (iii) Complex decomplexion and (iv)    solubility reduction methods of growing single crystals by gel.
  2. Outline the essential features of rubber like elasticity. Obtain the equation of            state for           the rubbering material.
  3. What is meant by symmetry operation? Describe point group and space group        symmetry        elements with necessary diagram.
  1. Explain the working of a p-n junction. Discuss forward and reverse biasing of p-n junction.
  2. Describe the behaviour and properties of conductors, insulators and semiconductors on the    basis of band theory.
  3. Write short notes on a) 1-2-3 oxides b) Chevral phases c) hard and soft magnetic materials.

 

 

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Loyola College M.Sc. Chemistry Nov 2006 Instrumental Analysis Question Paper PDF Download

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                        LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

M.Sc. DEGREE EXAMINATION – PHYSICS

AD 26

THIRD SEMESTER – NOV 2006

CH 3900 – INSTRUMENTAL ANALYSIS (FOR PHYSICS)

 

 

Date & Time : 03-11-2006/9.00-12.00     Dept. No.                                                    Max. : 100 Marks

 

 

PART – A

Answer ALL the questions                                                                            (10 x 2 = 20 marks)

 

  1. A sample of well water is found to contain 0.5000 g CaCO3 in 1 kg water sample.  Find out the concentration of calcium in mg mL-1.
  2. What is the pH of a solution containing 400 mg NaOH in 100 mL H2O.
  3. Explain red shift with an example.
  4. Mention the cell and detector used in IR spectroscopy.
  5. Compare the solubility of Agcl(s) in (i) pure H2O  (ii) 0.1 M aq. KCl and (iii) 0.1 m aq. KNO3.
  6. Mention factors which influence the quality of crystals obtained during recrystallization.
  7. How is adsorption different from absorption?
  8. What is retention factor in chromatography?  What is its significance?
  9. Why is low pressure distillation used to purify some compounds?
  10. Give the general principles of thermal analytical techniques.

 

PART – B

Answer any EIGHT questions                                                                 (8 x 5 = 40 marks)

 

  1. How is 1.0000 m HCl prepared from con. HCl?
  2. Drive Beer Lambert’s law.  How is it verified?
  3. Explain the principle of flame photometry.
  4. Determine the solubility of lead iodide in 0.0100 m aq. Pb(NO3)2 . Ksp of pbI2 is 1 ´ 10-10 mol3 dm-9.
  5. A solution containing 8.75 ppm KMnO4 has a transmittance of 0.743 in a 1 cm cell at 520 nm.  Calculate the molar absorptivity of KMnO4.
  6. What is the molarity of commercial H2SO4, containing 98% by weight with specific gravity 1.84 g mL-1.
  7. What is fractional distillation?  What are its advantages and limitations?
  8. Explain mobile phase, immobile phase, eluent and detection of compounds in paper chromatography.
  9. How is column for column chromatography prepared?  What are substances generally used to prepare these columns?
  10. How are compounds extracted from parts of plants?
  11. Discuss factors affecting DTA curves.
  12. Write notes on (i) sublimation (ii) thermometric titrations.

 

PART – C

Answer any FOUR questions.                                                     (4 x 10 = 40 marks)

 

  1. How is the pH of a solution determined using potentiometer?
  2. Draw the flow sheet diagram of UV-visible double beam spectrophotometer and explain the function of the components.
  3. (a) Draw the thermogram of CaC2O4.H2O(s) and explain.

(b) Explain the factors affecting thermogram.

  1. Explain steam distillation taking isomers of nitrophenol as examples.
  2. Write an essay on ion-exchange chromatography and its applications.
  3. Write notes on:

(i)  Molarity and Normality

(ii) Common ion effect

(iii)Thermal Conductivity Detector                                                                (3 + 3 + 4)

 

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