Colloids, Coarse Dispersions & Rheology

1. FOURTH SEMESTER B.PHARM PHYSICAL PHARMACEUTICS-II QUESTION BANK
Dr. A. SUMATHI, Professor & Head, Department of Pharmaceutics, SCPS, Trichy, Tamilnadu P a g e 1 | 1
FIRST SESSIONAL TOPICS - QUESTION BANK
I. Elaborate on (10 Marks)
1. Define and classify Colloids with suitable examples. Discuss their electrical properties.
2. Describe the various types of rheological systems with suitable rheogram and examples.
3. What is thixotropy. How is thixotropy measured. What is its significance in
pharmaceutical formulations?
4. Describe the various types of rheological systems with suitable rheogram and examples.
5. Explain different Non Newtonian flows with mechanisms, rheograms and examples.
6. Define viscosity. Explain thixotropy with rheogram. How will you determine flow
properties using Ostwald viscometer.
7. Define emulsion. Classify them and explain theories of emulsification with a neat
diagram.
II. Write notes on (5 Marks)
1. Differentiate flocculated suspension from deflocculated suspension
2. Describe Cup and Bop viscometer
3. Classify emulsifying agents with examples
4. Explain the stability of colloids by DLVO theory
5. Write a note on electrical double layer in colloids
6. Explain theories of emulsification
7. Write working principle of stalagmometer
8. Briefly explain the classification of colloids
9. Classify surfactants with examples
10. Explain electrical properties of colloidal dispersion
III. Short answers on (5 Marks)
1. Thixotropy
2. Glidants with examples
3. Half-life
4. Bulges and spurs
5. Coacervation
6. What is HLB scale?
7. Define gold number
8. Name two natural and synthetic suspending
agents
9. Explain the influence of temperature on viscosity
of liquid
10. What are shearing stress and rate of shear?
11. What are the causes for creaming in an
emulsion? (or) Define creaming of emulsions
12. Explain the Stokes equation for settling of
particles in suspension
13. What is a pseudo plastic system?
14. Freaundlich equation for adsorption at
solid interface.
15. Plug flow
16. Peptization in colloidal dispersions
17. What is kinematic viscosity?
18. What is surface free energy?
19. What is spreading coefficient?
20. How to achieve controlled flocculation
in a suspension?
21. What are detergents?
22. What are Newtonian systems?
23. Brownian movement
24. Tyndall effect of colloids
25. What are protective colloids?
26. What is dilatant flow? Give example.
27. What are structured vehicles?