Guru Nanak Dev University 2005 B.Sc Chemistry PHYSICAL (Chem-203) -2k5 - Question Paper

B.Sc in Chemistry second Semester
2045
Chem - 203
Physical Chemistry

Time allowed : three hours

Maximum Marks : 75

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

part - A

1. Differentiate ranging from ideal gases and real gases.

2. describe the terms : avg. velocity, root mean square velocity and most probable velocity.

3. What is the avg. kinetic energy of 1 mole of nitrogen gas at 25º C ?

4. elaborate liquid crystals?

5. How many atoms are current in simple cubic and face centred cubic unit cells ?

6. describe sol, gel and emulsions.

7. Water has a dipole moment of 1.85D, while CO2 has zero dipole moment. discuss.

8. Distinguish ranging from equivalent conductance and specific conductance.

9. discuss the term optical activity.

10. describe solubility product of a sparingly soluble salt.

1½ x 10

Setion - B

1. discuss why do the gases show cooling effect in adiabatic expansion. How can this effect lead to the liquification of gases?

2. Deduce expressions relatyed to the critical constants of gas in terms of van der Waals constants.

3. provide a brief account of Kinetic theory of gases.

4. Collision diameter of oxygen molecule is 361 pm at 27º C. compute the mean free path at one atm pressure.

5. Differentiate ranging from various kind of liquid crystals. Show diagramaticaly the molecular arrangemants of different kinds of liquid crystals.

6. State and discuss the laws of crystallography.

7. discuss why :
(a) Gelatin prevents the precipitation of colloidal solutions.
(b) Alum is used in town water supply.
(c) Deltas are formed at a place where rivers merge in the sea.

8. provide a brief account of the Claussius-Mossotti formula.

9. describe dipole moment. How will you measure the dipole moments in solutions.

10. State and discuss Kohlraush's legal regulations.

11. The resistance offered by 0.1 N KCl and 0.1 N AgNO3 solutions is obtained to be 307 and 368 ohms respectively at 25º C. compute the equivalent conductance of 0.1 N AgNO3 solution. (Specific conductance of 0.1 N KCl solution at 25º C is 0.01286 ohm-1).

12. Write short note on conductometric titrations.

4½ x eight = 36

part - C

Earning:   Approval pending.