Rol; olbhiNo. Total Pages : 03 CMDQ/M-19 2642 PHYSICAL CHEMISTRY SPECIAL-III CHEM-401 Time : Three Hours] [Maximum Marks : 60 Note : Attempt Five questions in all, selecting at least one question from each Section. All questions carry equal marks. Section A 1. (a) Mention some degradable polymers with its applications. 6 (b) @ What are Dendrimers 2 Discuss its application. 3 (ii) What are the Plasticizers ? Give some 3 examples. Write the different types of polymer 2 (a) @ composites. 2 (ii) Discuss some applications of polymer based composite materials. 3 P.T.O. 3-54/5) L-2642What information docs the glass tray Si hi Explain Zimm plot method for the molecular weight ® @ temperature (T;) tell about a polymer sya (a) | determination. Compare with Debye method. = @ (i) Discuss the effect of molecular Weight E| (b) Discuss in brief the principle of Gel permeation glass transition temperature. 1 chromatography for molecular weight determination of polymer. 4 Section B Section D end-to-end distance and rms. sag, l Given that B;(T) = 463 —26; and 6Vé; =Z;-3Z,Z2=+2Z7 3. @ Define rms. of gyration. How are they related ? } by freely jointed chain ? Dig 5) What is meant Cus = : : a : : effect of bond angle restriction. “4 and 2Vby = (Zz ~Z?) . Derive expression for B(T) in terms fo Explain the concept of excluded volume as app, of Mayer Jfunction. Also, draw the cluster diagram to dilute polymer solutions. a corresponding to obtained product of functions. 2 4 @ What do you understand by the lattice mode gq® () Show that distribution function, p\ (7) is equal to liquids ? Under what condition can this be app ied! density of a fluid. + to polymer solution ? 4) (©) Derive the expression for energy of N-body system (b) Describe Flory-Haggim theory to explain dilute in terms of correlation function. 8 polymer solution. i Section C 5. (a) Describe the method of determining of molecul weight by a high speed osmometer. (®) Discuss the phenomenon of light scattering 6 | 100 polymer solutions. (-54/6) L-2642No. -- Total Pages : 04 CMDQ/M-19 2643 PHYSICAL CHEMISTRY SPECIAL-IV CHEM-402 >: Three Hours} : [Maximum Marks : 60 2; Attempt Five questions in all, selecting at least one question from each Unit. All questions carry equal marks. Unit I (a) Explain how could band theory of solids account for difference in electrical conductivity of solids.4 (b) The resistivity of aluminium at room temperature is 2.62*10-8 ohm-m. For conduction electrons, calculate relaxation time and mean free path on the classical free electron theory. Density of basis of 4 aluminium is 2700 kg m?. (c) Explain the difference between direct and indirect band gap semiconductors. 4 4 the wroking of metal- semiconductor -bias, forward-bias e-bias conditions. 6 p.T.0. (a) Explain for all different cases. junction under no: and revers 8/12) L-2643) © 3. @ () © @ 12643 What do you understand by Fermi eng | does it change with doping conan j temperature ? ion ‘A simple of silicon is made n-type sen; by adding donor atoms at the rate of need 4x108 silicon atoms. The intrinsic oes concentration is 2.5*10!9 m3 at 300 a the concentration of holes with inna carers. Given that at 300 K all donor BS jonized and density of silicon atoms is 4.4 mm. Unit 1 Explain how the design of solar-cells based $i, a-Si and GaAs different ? ‘A solar cells has the following parameters’: (b) © @ @ ) Se ae What are the advantages and disadvantages of concentrator photovoltaics 7 3 What are the parameters used to characterize batteries 7 3 How does memory effect lower the output efficiency 2 of batteries ? Unit What is the difference between the following = () Three-electrode and two-electrode setup (ji) Polarizable and non-polarizable electrodes. 4 “What are the various processes through which mass: ecingport occur in =, spstamn . Wha ae BSS" token tp minimize the effect of wmemisted: factors during any electrochemical study ? 6 0.7 V, ly = 25 mA/em? and FF = 70%. Whal (©) At300 K the exchange current density for a reaction be its efficiency ? on nickel surface is 10 mA/em?. Calculate the Discuss in brief, the thermodynamic limit of| coment density required to attain an overpotential conversion efficiency. of 100 mV using Butler-Volmer equation. Assume How is back surface field used to improv transfer coefficient to be 0.50. 2 conversion efficien: ey of solar cells ? (@) Discuss the cyclic voltammograms for reversible With the lp of energy level diagram, expla and ireversible electrochemical reactions. 3 working of dye-sensitized solar cell. (b) What is Tafel plot and its significance ? 2 2 (2-68/13) L-2643 3 P.T.O.(©) @ (a) (b) (a) (b) (©) Explain electrocatalysis with an example, Discuss different types of Nyquist plots that en 4 b obtained for electrochemical system. Unit IV Write short notes on the following : (ij) Electrochemical sewage disposal (ii) Electrochemical reduction of CO, (iii) Electrochemical of water-splitting. Discuss different forms of corrosion. What are ion-selective electrodes ? Explain th working of any one ion-selective electrode in detail ( What should be the properties of membran electrodes ? Discuss alkaline and acid error for glass electrodeTotal Pages : 03 oll No. « ty CMDQ/M-19 2644 PHYSICAL CHEMISTRY | CHEM-CH-403 4 Special V “hme : Three Hours] [Maximum Marks : 60 Note; Attempt Five questions in all, selecting at least one question from each Section. All questions carry equal marks. Section A (@) List the type of physical and chemical changes that can yield endothermic and exothermic pears in DTA and DSC. (b) Explain different types of thermogravimetry. Discuss j different factors affecting thermograms. | (©) Why does the. glass transition for polymer yield no f exothermic and endothermic peak ? (d) How the purity of drug can‘be established using DSC ? Illustrate your answer by taking sample of drug phenacetin ? 3,4,3,2 | 78/3) L-2644 P.T.O. Lor»2 @ ) @) © ) 12644 — eserbe the difference between Power com, < and neat flux DSC instruments. “sy Derive the general equation of multiple heating \ methods from TG curve. Why multe 41 methods are superior than single beating | methods ? Section B Why the properties of nanomaterials are dif, from properties bulk materials ? Using examples describe the synthesis nanoparticles using : @- MOCVD (ii) Sputtering methods. Discuss applications of nanomaterials. 3, What do you understand by photolithography Discuss its importance in semicondu manufacturing | Discuss in detail electric and mangnetic Propet of nanomaterials. Section C @ _ Explain Grotthus-Draper law of photochemistry. (b) What are charge transfer transition ? (© Discuss excinnet and exciplex formation. 2,4,6 @ Derive Stern Volmer equation of photochemistry. (&) Discuss the applications of LASER in photochemical Kinetics. () What is difference fluorescence and delayed fluorescence ? 6.42 Section D (@) Discuss the irreversible thermodynamics treatment of membrane transport. (b) What do you understand by muscular contraction and energy generation in mechanochemical system ? 66 Write short notes on the following : (@) Absorption spectroscopy (b) Fluorescence spectroscopy (b) Linear and circular dichroism. 43 78/4) L-2644 3 100Total Pages : 03 CMDQ/M-19 2645 PHYSICAL CHEMISTRY (Special) CHEM-404 Paper VI DEL INUg ssssesenennens ime : Three Hours] [Maximum Marks : 60 ‘ote : Attempt Five questions in all, selecting at least one question from each Section. All questions carry equal marks. Section A (a) Write briefly about the validity of unimolecular reactions. (b) Discuss the application of activated complex theory on reactions between atoms. 5,7 Write an account of Marcus’s extension of RRK @ treatment (RRKM), for a unimolecular reaction. (b) Wriet a note on ‘Thermodynamic aspects of reaction rates’. 8,4 3-54/) 45; P.T.O.3. @) ) © by ) © @ L-2645 eT tee Peers ce ) Discuss the kinetics of hydrogen-oxygen explosion & What is meant by molecular beams 2 Writ reaction. 6,6 principle of crossed-molecular beams. i sans Discuss the dependence of collisional cross seeg oo eee nee a. {@)_Disouss basic types and structures of liquid crystals Explain the following : (p) What are lyotropic phases ? How are they formed ? ee eee Describe the molecular ordering of a lameller phase 2 Gi) Reaction cross-section. 66 What are Cholesteric Liquid Crystals ? Discuss the optical properties of cholesteric liquid crystals (b) Discuss briefly about homeotropic, planar and the ions. What happens -in a medium of fininite schlieren textures. 18 dielectric constant 2 a Describe the mechanism and Kinetics of enzymes. (a) catalyzed reaction. : Determine the rate constant for a reaction betwee, Section C Explain, how apparent activation energy of chain reactions is determined ? Discuss the theory of branching chain reactions. What are the disadvantages of ‘Flow Methods’ ? 5,5,2 Describe the experimental set up and working of temperature-jump technique. What are the factors affecting heating time (<¢). \ 2 3-54/8) L-2645 3 00, ave a