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I;,

9 Code No. 34( English Version)

Instructions: i) The question paper has Jour Parts.It ) Parts A, B, C and Dare common to all the candidates.iii) Part A carries 10 marks. Each question carries one mark.

Part B carries 20 marks. Each question carries two marks.Part C carries 40 marks. Each question carries five marks.In Part D - D 1 carries 10 marks and D 2 carries10marks. Each question ofD 2 carries Jive marks.

iv) Write balanced chemical equations and draw diagramswherever necessary.

PART-A

Note: i) Answer all the ten questions.ti ) Questions have to be answered in one word or in one

sentence each. Each question carries one mark.10 x 1 10

1. What is the gas liberated at anode in the manufacture of caustic sodausing Nelson cell ?

2. A noble gas is preferred to hydrogen gas in filling air-ships. Name thenoble gas.

3. Twoatomic orbitals undergo asymmetric combination byLCAO.What typeofmolecular orbital is formed? .

4. What is the effect of a positive catalyst on the 'energy of activation' of areaction?

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Code No. 34 105. Howmany gram equivalents of oxygengas is liberated when two faradays

ofelectric current is passed through acidifiedwater?6. What is 'Osmotic pressure' ?7. GiveSIunit for 'entropy'.8. Write the IUPACname of ( CH3) 2 CH- CH2 - Cl.

9. Which one of these has lower pKavalue, nitrophenol or phenol?10. Write the Haworth's structure of a-D (-) fructopyranose.

PART - B

Note: i} Answer any ten questions.n) Each question carries twomarks. 10 x 2 = = 20

11. Mention the roles of (i) Calcium carbonate, (ti) Carbon monoxide in themetallurgy ofiron.

12. What happens when sulphur dioxide gas is passed into acidifiedpotassium dichromate solution? Givethe equation.

i) givethe IUPACname

13. 3d block elements showvariable oxidation states. Givereasons.14. For [CoCI 2 ( en )2 ] Br

ti l what type of structural isomerism does it exhibit?15. Assuming complete ionisation, calculate the pOH of 00025 MBa( OH ) 2

solution.

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11 Code No. 3416. Draw a neat labelled diagram of SHE. Give its symbolic representation.17. Classify the following into lyophilic and lyophobic sols:

i) Starch sol ti) Sulphur soliii) Fe (OH )3 sol iv} Gelatin sol.

18. How is the order of the reaction A + B ~ products, determined byOstwald's isolation method?

19. Identify P, Q, R, S in the following conversions:CH 3Cl _ _ _ _ f _ ~ CH3CN Na/alcohol HNO2 acid KMnO4Q 00C ~R ----~S

20. Howis benzaldehyde converted into Cinnarnic acid? Give the equation.21. i) Write the equation for the rate determining step involved in the

mechanism of the hydrolysis oftertiary butyl bromide.ti ) Give the general equation for Hoffmann's bromamide reaction.

22. What are antibodies? Howdo they function?

PART - C

1. Answer any two of the followingquestions : 2 x 5 = 1023. a) How are argon, krypton and xenon separated from one another

from a mixture of noble gases in Dewar's process? 3b) Write the energy level diagram for the orbitals in lithium

molecule. What is its bond order? 2

24. a) On the basis of Valence bond theory', account for the geometryof 'ferrocyanide' ion. 3

b) What are the conditions employed in the Haber's process toincrease the yield of ammonia ? 2

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Code No. 3425. a)

12Describe 'electron sea model' for metallic bond. 2

b) Give the electronic configuration of Mn + 4 ion. Is the ionparamagnetic or diamagnetic? Give reason. 2

c) When sulphur trioxide is absorbed in 98% sulphuric acid.what is obtained? 1

3 x 5 = 15I. Answer any three ofthe followingquestions:26. a) Howis methyl chloride converted into Crtgnard reagent and how

is the Grignard reagent obtained converted into acetic acid ?Giveequations. 4

b) An a-amino acid can form disulphide bond. Name the a-aminoacid. 1

27. a) Give the steps involved in the mechanism of Friedel-Craftsalkylation ofbenzene. Givetheir equations. 3

t i l What are enantiomers ? 2b) i) Write the structure of cis-2-butene.

b) Write the equations for the followingreactions: 2

28. a) What is 'iodine value' for an oil or fat? Drying oils have highiodine value. Why ? 2

i) Vapours of isopropyl alcohol is passed over heated coppercatalyst. .~

ti) An aldehyde is treated with hydrogen cyanide.c) Howmany tc bonding molecular orbitals are filled in benzene? 1

29. a) What is 'electromeric effect' ? What polar effect of the aminogroup makes aniline a weaker base than ammonia? 2

b) With equation, givecarbylamine reaction for methylamine. 2c) Sketch the 'chair conformation' of cyclohexane. 1

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13 Code No.343 x 5 = 15II. Answer any three of the followingquestions:

30. a) DertveHenderson's equation for an acidic buffer pH. 3b) Write the proton transfer reaction ( with equation between

nitric acid and ammonia. Identify a conjugate acid base pairfurmed. 2

31. a) Applying the principles of solubility product and common ioneffect, explain why II and IV group basic radicals areprecipitated as their sulphides in acidic and basic mediumsrespectively. 3

b) i) Define'Coordination number' for an ionic crystal.ii ] What type of crystalline solid is ice? 2

32. a) Define 'vapour pressure of a liquid'. Which one of the followingsolutions shownegative deviation fromRaoult's law? .i) Ethanol +Waterti) HCI + Water. 2

c) What is Tyndall effect ? 1

b) Calculate the electrode potential ofhydrogen electrode at 298 K,when the pressure of hydrogen gas is one atmosphere and theconcentration ofhydrochloric acid is 10- 3M. 2

33. a) i) What is peptization ?Givean example.

meets the sea. Givereason. 3Ii ) Delta regions are formed in the places where river water

b) Vapour pressure of pure water at 298 K is 33 kPa. Calculatethe relative lowering of vapour pressure of an aqueous solutioncontaining 20 g of glucose dissolved in 90 g ofwater at 298 K.Molecular mass ofglucose = 180. 2

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Code No. 34 1434. a) Mention four factors on which the conductivity of a solution

depends. 2b) i) What happens to the pH of acetic acid solution when solid

sodium acetate is dissolved in it ?ti] What is the composition of 'rust' ? 2

c) Temperature coefficient of a reaction is two. By how many timesdoes the rate of the reaction increase if the temperature of thereaction is raised from 340 Kto 380 K ? 1

PART - DDl

IV. Answer anyone of the following : 1 x 10 = 1035. a)

\""0\500- 2'000'----"7 'I\~The graph shows Ellingham diagram for the formation of CO,HgO. Alz a 3 and Cr z 0 3' Using the Ellingham curves explainwhyi) aluminium (Al 1 can reduce Cr z 0 3t il stability ofcarbon monoxide increases with temperatureiii) mercury (Hg)can be obtained by the thermal decomposition

of HgO, 3

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15 Code No. 34b) i) Glucose reacts with hydroxyl amine to form a mono-oxime

and glucose also reacts with acetic anhydride to form apenta-acetyl derivative. What inference can be drawn fromthe above observations regarding the structure of glucose?

ti ) Write the general equation for the formation of a 'mixed

c) i)

triglyceride'.Equilibrium constant (Kp) for the reaction

X + Y ~ P + Q at 300 K is 35 x 10 - 4. Calculate the.

3

standard free energy change for the reaction at 300 K.Under the given conditions, is the reaction spontaneous ?Give reason.

ti) Howmany formula units of sodium chloride ( NaCI ) arepresent in a unit cell of sodium chloride crystal ? 4

i) Give any two differences between primary and secondaryvalencies of a metal that forms a coordination compound.

36. a)

ti l At 800C, by how many times is silver more soluble inmolten zinc than in molten lead? 3

b) How is phenol manufactured by ournene process ? Giveequations. 3

c) Half-life period for the reaction at 298 K of A ~ products is333 hours. Calculate the rate constant of the reaction. If thereaction is started from one mole of A, what amount of Aremains unreacted at the end of 9 (nine 1 hours? Calculate. 4

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Code No. 34

V. Answer any two ofthe following: 2x5=10

37. a) In the preparation ofm-dinitrobenzene fromnitrobenzene:

i) name the reagents used

t il write the equation for the reaction involved

ill) what is the colour of the product? 3

b) Few drops of coconut oil is heated with sodium bisulphatecrystals. What is the observation made? Name the test. 2

solution. Give the equation for the redox reaction. 5

38. Describe the experimental procedure and give the calculationsinvolvedin the estimation of the amount of potassium permanganatepresent in one dm 3 of its solution using standard oxalic acid

experiment? 5

39. Describe the experiment to determine the effect of temperature onthe rate of the reaction between potassium persulphate andpotassium iodide. What is the conclusion drawn from the