Guru Nanak Dev University 2007-2nd Sem B.Sc Chemistry PHYSICAL (CHEM-203) (-2k7) - Question Paper

2057

B.Sc. (Hons. School) in Chemistry second semester

CHEMISTRY

Paper : CHEM-203

(Physical Chemistry)

Time Allowed : 3 Hours
Maximum Marks - 75

Note :- Attempt ALL ques. from Section-A, 8 ques. from Section-B and 2 ques. from Section-C

part - A
(10 x 1½ = 15)

1. discuss the critical phenomenon applied to the gaseous state.

2. explain most probable and avg. speed.

3. Write the expression for Debye-Huckel-Osnager formula. discuss the terms used in it.

4. Show graphically how equivalent conductivity of strong and weak electrolytes vary with the change in concentration.

5. What is Hardy-Schulze rule ?

6. The specific conductance of a decinormal solution of KCl at 18ºC is 1.12 Sm-1 (inverse). The resistance of the cell containing the solution at the identical temperature was obtained to be 55 ohms. What is the cell constant in cm-1 (inverse) ?

7. compute the angle at which the 1st order diffraction will occur in an XRD when X-Rays of wavelength 1.54 Å are diffracted by atoms of crystals. The interplanar distance is 4.04 Å.

8. discuss dipole moment.

9. discuss the difference ranging from face-centered cubic unit cell and body centered cubic unit cell.

10. List different symmetry elements in a cubic crystal.


part - B
(8 x 4½ = 36)

1. discuss root mean square velocity of hydrogen molecule at N.T.P (Given : density of Hg = 13.6 gm/cm3 and acceleration due to gravity is 981.0 cms-²).

2. Deduce an expression for decreases formula of state.

3. What is Ostwald's dilution legal regulations ? provide its limitations.

4. Derive Claussius-Mossoti formula.

5. provide an account of qualitative description of structure of liquids.

6. explain the process of liquifaction of gases based on Joule-Thompson effect.

7. discuss the limitation of Arrhenius theory of electrolytic dissolution.

8. define the phenomenon of Tyndall effect.

9. What is an emulsifier ? discuss its role.

10. elaborate the various laws of crystallography ? discuss.

11. define the process of conduction in electrolytes.

12. refer to attachment


part - C

1. elaborate the factors which led ideal gas formula to be replaced ? Derive van der Waals formula of state. provide significance of van der Waals constant. (5, 5, 2)

2. (a) elaborate liquid crystals ? How are they classified ? define their applications. (8)
(b) define powder method for the determination of crystal structure of solids. (4)

3. elaborate colloids ? How are they classified ? Justify the statement that they play a vital role in our daily life. (4, 4, 4)

4. (a) elaborate conductometric titrations? Depict the nature of conductometric titrations when (i) strong acid is titrated against a strong base and (ii) weak acid is titrated against a strong base. discuss the observed modifications. (8)
(b) refer to atachment

Earning:   Approval pending.