Chemistry pass 2nd sem 2014 previous year Bsc question paper | Assam University

Chemistry pass 2th sem 2014 previous year Bsc question paper | Assam University

2014 

TDC Even Semester Exam., 2014 

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 th mwgin indicate full marks for the questions 

GROUP—A 

( Inorganic Chemistry) 

(Marks: 12) 

Answer one question from each Unit 

UNIT—I 

1. Define electronegativity. Give a short account of Pauling’s scale of electrongtivity. 1+2=3

2. Write briefly about ‘diagonal relationship’ and ‘ionic radius’.

UNIT—Il 

3. (a) Explain Cady and Elsey’s concept of an acid and a base.
(b) Ammonjum chloride behaves as an acid in liquid ammonia. Explain.
4. (a) IuThe alkali metal solutions in liquid ammonia are blue in colour and the solutions are highly paramagnetic.” Comment.
(b) Give one example of solvolysis rcaction in liquid sulphur dioxide.

UNIT—Ill 

5. How is hydroxylamine prepared? Give one reaction each to show its oxidizing and reducing properties.

6. (a) Why diamond is hard whereas graphite is soft?
(b) Discuss the structure of fullerene (C60). 2

UNIT—IV 

7. (a) What is the main cause of ‘lanthanide contraction’?
(b) Discuss its. effects on the properties of lanthanides.
8. (a) Give the names of two lanthanides. What are the oxidation staLes exhibited by them?
(b) Name the lanthanide which radioactive.

GROUP—B 

(Organic Chemistry) 

( Marks : 11) 

Answer one question from each Unit 

UNIT—I 

9. What is the chemical composition of coal? Which variety of coal is particularly rich in aromatics?

10. What is petroleum? Why has it been named as liquid gold?

UNIT—Il 

11. (a) What is meant by directing influence of a group or atom in the benzene nucleus?
(b) Which of the following groups are orthaa nd para- or meta-directing? Give reasons
(i) —NH2
(ii) —c—-oii

12. Write, in detail, the mechanism of chlorination of benzene.

UNIT—Ill 

13. (a) Give the composition and mention one use of Lucas reagent.
(b) Write the mechanism of dehydration of alcohol.

14. What happens, when
(a) phenol is heated with chloroform and caustic soda; 1
(b) phenol is heated with a mixture of conc. HNO3 and conc. H2S04?

UNIT—IV 

15. (a) What are nucleophilic addition reactions?
(b) Why are aldehyde more reactive than ketones in a typical nucleophilic addition reaction? 2
16. (a) Illustrate with suitable example the rnechauiui of aldol condcnoation reaction.
(b) Write any one gcnezd method of preparation of ketones.

GROUP—C 

(Physical Chemictry) 

(Marks: 12) 

Answer one question from each Unit 

UNIT—I

17. (a) Indicate which among the following functions are state functions of a thermodynamic system :
(I) Internal energy
(ii) Work done by a system
(iii) Heat absnrhd
(iv) Entropy
(b) What do you mean by path function?

(6)
18. (a) What do you mean by work’ of a thermodynamical system?
(b) Distinguish between reversible and irreversible processes.

UNIT—II

19. (a) What is inversion temperature?
(b) For an adiabatic expansion of 1 g mole of an ideal gas = constant. Prove this statement.

20. One mole of an ideal gas expands isothermally and reversibly from 1 litre to 100 litres at 27 °C. Calculate w, q, AE, iH and iSS for thc proccss.

UNIT—IlI

21. (a) State phase rule and define the terms involved.
(b) What do you mean by phase diagram.

22. Calculate the number of phases, number of components and degrees of freedom for the following
(a) For a dilute solution of H2S04 in water
(b) For a liquid at its critical point
(c) For the reaction
N2 (g)+3H2 (g)2NH3 (g)

UNIT—IV 

23. (a) Define van’t Hoff factor. 1
(b) What is the boiling point of solution containing 5 g urea (M=60) in 100 g water? (Given K b =0.513)

24. (a) What is osmosis? 1
(b) Calculate the osmotic pressure of human blood it it is isotonic with 09% NaCI solution at 27 °C. (Given a for NaCI is025).

14J—1400/1164 (A/B/C)/283