Chemistry pass 2th sem 2015 previous year Bsc question paper | Assam University
2015
TDC Even Semester Exam., 2015
CHEMISTRY
(Pass)
( 2nd Semester )
Paper No. : CHMP-201
( Inorganic, Organic and Physical Chemistry)
Full Marks: 35
Pass Marks : 12
Time : 2 hours
The figures in the margin indicate full marks for the questions
GROUP- A
( Inorganic Chemistry )
(Marks: 12)
Answer one question from each Unit
UNIT I
1. (a) Explain the significance of 2
(b) Using Slater’s rule, calculate the effective nuclear charge for the valence electron of copper atom.
2. (ci) Explain why Pb4 salts are more oxidizing than Sn4 salts.
(b) Compare electron affinities of F and Cl and justify.
UNIT—Il
3. Give examples and discuss (a) complex formation reactions and (b) neutralization reactions in liquid ammonia. 1 Y2+ 1 V
4. What are hard and soft acids and bascs? Give suitable examples.
UNIT—Ill
5. (a) Write Raschig’s method of synthesis of hydrazine.
(b) What happens when sodium azide is heated above 300 °C?
(C) How do you account for the greasiness of graphitc?
6. (a) Draw arid describe the structure of C.
(b) Write the products of the lollowing reaction
AgNO3 +N2H4 —?
UNIT—IV
7. (a) What are lanthanides? Why are these also called inner-transition elements?
(b) How do you account for colour of lanthanide compounds?
8. (a) What are the different oxidation states of lanthanides? Discuss relative stabilities of the states.
(b) How do you account for lanthanide contraction?
GROUP—B
( Organic Chemistry )
( Marks : 11)
Answer one qut.stiuii fiuin each Unit
UNIT—I
9. (a) Name two products of carbonization of coal and mention their usefulness. 1
(b) Write note on synthetic petrol. 1
10. (a) Explain the term ‘cracking’. 1
(b) How did coal originate? 1
UNIT—Il
11. (a) Discuss the mechanism of nitration of benzene.
(b) Explain the directive influence of —NH2 group.
12. (a) Write the mechanism of suiphoriation of benzene.
(b) Explain activation-deactivation in electrophilic aromatic substitution taking suitable examples.
UNIT—Ill
13. (a) Explain hydroboration reaction and point out its utilities. 1+11
(b) Write a brief note on Fries rearrangement.
14. (a) Write with equaliun how you can synthesize 30 alcohol using Grignard reagent.
(b) Write the test to show that phenols are more acidic than alcohols. Give necessary explanation.
(5)
UNIT—IV
15. (a) Which of the following is more reactive towards nucleophilic addition reaction and why? Butanal, Butanoneb) Write the mechanism nf C1isen condensation.
16. (a) Write one general method of synthesis of aldehydes.
(b) Write the mechanism of addition of NaHSO3 to carbonyl compounds. 2
GROUP—C
( Physical Chemistry)
(Marks: 12)
Answer one question from each Unit
UNIT—I
17. (a) Explain, with examples, how extensive properties differ from intensive properties.
(b) What is a perfect differential? Explain.
(6)
18. (a) Bring out the difference between ‘open system’ and ‘closed system’ with examples. 2
(b) Write the thermodynamic notations for
(t) adiabatic process and (ii) isochoric process. Y2+Y21’
UNIT—II
19. (a) Show that work done by a system in a reversible isothermal expansion of ideal gas is greater than that in an irreversible expansion. 2
(b) What is Joule-Thomson coefficient?
20. (a) Two moles of ideal gas expand isothermally and revtrsib1y at 27 °C from 1 m3 to2 m3. Calculate w, q, E and tH.
(b) Define the term ‘enthalpy’.
UNIT—III
21. (a) Draw and discuss the phase diagram of carbon dioxide. 2
(b) What is a metastable equilibrium? 1
(7)
22. (a) Derive Gibbs’ phase rule thermodynamically. 2
(b) Find the number of phases, components and degrees of freedom for the following: An aqueous solution of glucose
UNIT—IV
23. (a) An aqueous solution of a non-volatile solute boils at 10017 °C. At what temperature would it freeze? For water, Kb =052 Kkg moF1 and K1 = 186 Kkg mo11. 2
(1) What are isotonic solutions?
24. (a) State and explain Raoult’s law of lowering of vapour pressure. 2
(b) What are abnormal colligative properties?
I 5—19 10/1197 A—I 5/EVEN/CHMP-201 (A/B/C)/251
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