Physical pharmaceutics-II MCQs on coarse dispersion Sem-04

1. COARSE DISPERSION
Physical Pharmaceutics-II
APRIL 27, 2021
GOURAV SINGH

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Suspension
1] A wetting agent is included in the formulation of a suspension, particularly when
the suspended particles:
a. are hydrophobic
b. are more denser than the vehicle
c. are water soluble
d. have lesser interfacial tension
2] For a flocculated suspension, one of the following criterion is satisfied or
established
a. High inter-particle repulsions
b. strong inter-particle attractions
c. weak inter-particle attractions
d. weak inter-particle repulsions
3] In stokes’ relationship, a parameter that greatly changes the velocity of settling is:
a. density of the liquid
b. density of particle
c. radius of the particle
d. viscosity of the medium
4] The protamine-zinc insulin suspension is prepared by a method viz.,:
a. altered pH precipitation
b. dispersion method
c. double decomposition
d. organic solvent precipitation
5] Methyl cellulose is a polymer, which is of a type:
a. anionic
b. amphilytic
c. cationic
d. non-ionic
6] For a flocculated suspension the degree of flocculation is observed to be one. The
sedimentation volume is also 1 (one). These values, respectively, indicate the limits:
a. lower and lower
b. lower and upper
c. upper and lower
d. upper and upper

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7] For an ideal suspension, the sedimentation volume should be:
a. equal to one
b. less than one
c. more than one
d. zero
8] In case of suspensions, all statements below are true EXCEPT that:
a. it contains a suspending agent
b. it does not include a preservative
c. it is an injectable preparation
d. it is an oral preparation
9] In practice, an acceptable suspension should have particles:
a. of nearly 0.1 micrometer
b. which can be readily re-dispersible after they settle
c. which should form a cake after settling
d. should not settle
10] For oral administration of a suspension to a patient, which one of the factors is
the most important?
a. acceptable color and odour
b. polyumorphism
c. specific surface area
d. viscosity
11] Which one of the following properties is applicable to suspensions?
a. Brownian movement
b. laminar flow
c. rapid rate of sedimentation
d. strokes’ law
12] Suspended particles become flocculated in a suspension, because:
a. attractive forces between particles are appreciable
b. particles are packed closely
c. repulsive forces between particles are appreciable
d. vehicle rejects the particles
13] Structured vehicle is included in the formulation of a suspension, in order to:
a. decrease the interfacial tension
b. prevent the caking of the sediment
c. prevent the sedimentation of particles
d. reduce the size by chemical means

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14] In the preparation of a structured vehicle, which one of the following substances
is used?
a. bismuth subnitrate
b. ethyl alcohol
c. glycerin
d. methyl cellulose
15] Which type of colloidal material is used commonly in the preparation of a
structured vehicle?
a. association
b. hydrophilic
c. hydrophobic
d. inorganic
16] When charcoal powder is dusted on the surface of water, the contact angle (in
degrees) that the charcoal exhibits is:
a. zero
b. one
c. 90
d. 180
17] A maximum sedimentation volume will be obtained when zeta potential is:
a. negative
b. neutral
c. positive
d. zero
18] A substance is dissolved in water. The suspension has exhibited a negative
apparent zeta potential.
Identify the related substance.
a. aluminum chloride
b. bismuth subnitrate
c. gelatin
d. sulfaguanidine
19] Calcium hydrogen phosphate is dissolved in water. The apparent zeta potential
initially is:
a. negative
b. neutral
c. positive
d. zero
20] Which one of these preparations is NOT qualified as a suspension.
a. barium meal for radiodiagnostic use

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b. calamine lotion for antiseptic use
c. procaine penicillin G for intramuscular injection
d. vitamin B complex tonic as nutritional supplement
21] The ratio of the ultimate volume of sediment to the actual volume of sediment
before settling is called
a. Sedimentation volume
b. Degree of flocculation
c. Emulsification volume
d. phase volume ratio
22] The ratio of the sedimentation volume in case of flocculated suspension to the
sedimentation volume in case of deflocculated suspension is called
a. Sedimentation volume
b. Degree of flocculation
c. Emulsification volume
d. phase volume ratio
23] The size of dispersed particles in coarse dispersion ranges from
a. 1 µm to 100 µm.
b. 1 nm to l00nm
c. 1mm to 100cm
d. Less than 1 µm
24] Which of the following are the desired features of good suspension:
a) The particles which settle down should not deposit at the bottom as hard cake. They
must be easily re-suspended by moderate shaking.
b) It should be free from grittiness.
c) It should be stable in case of physical, chemical and microbial attack.
d) All of the above
25] In flocculated suspension, the rate of sedimentation is
a. Low
b. More
c. Zero
d. 50%
26] If zeta potential of a suspension is high, then the system will be considered as
a. Deflocculation
b. Flocculation
c. Emulsion
d. Sedimentation

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27] Which of the following is/are the properties of flocculated suspension?
a. Rate of sedimentation is high
b. On shaking sediment can be easily redispersed
c. It does not form hard cake
d. All of the above
28] The value of sedimentation volume (F) gives a knowledge about the____________
of the suspension
a. physical stability
b. Incompatibility
c. Solubility
d. All of the above
29] Suspension is example of
a. Biphasic liquid dosage form
b. Solid dosage form
c. Semi-solid dosage form
d. All of the above
30] Acetates and Citrates are
a. Buffering agent
b. Coloring agents
c. Thickening agent
d. Flocculating agents

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Emulsion
1. In an emulsion, the velocity of sedimentation is found to be negative. It means that
the creaming is:
A. absent
B. in both the directions
C. in downward direction
D. in upward direction
2. The density of the dispersed phase is more than that of the dispersion medium.
According to the Stokes’ equation, the creaming is:
A. at the center of the emulsion
B. in both the directions
C. in downward direction
D. in upward direction
3. When oil and water are triturated together, the interfacial free energy was observed
to be increased. What does it indicate?:
A. decrease in the interfacial tension
B. decrease in the stability
C. increase in stability
D. stable film formation
4. For a stable emulsion, the phase volume ratio is generally about:
A. 26/74
B. 52/48
C. 74/26
D. 74/100
5. The HLB range of an emulsifier employed in the preparation of water-in-oil
emulsion is:
A. 3 to 6
B. 7 to 12
C. 13 to 15
D. more than 15
6. In case of emulsions, the viscosity immediately after preparation and during
storage, respectively, will be:
A. higher and will gradually decrease
B. higher and gradually increase
C. lower and gradually decrease
D. lower and gradually increase
7. The distribution of globules is not uniform in an emulsion. This stage is termed as:
A. breaking
B. caking

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C. coalescence
D. creaming
8. An o/w microemulsion is prepared using a hydrophilic surfactant. The appearance
of the microemulsion is:
A. intense white
B. milky white
C. translucent
D. transparent
9. Emulsions are defined as thermodynamically unstable systems. The events that
follow sequentially towards instability are:
A. coalescence, breaking, creaming and flocculation
B. coalescence, flocculation, creaming and breaking
C. flocculation, creaming, breaking and coalescence
D. flocculation, creaming, coalescence and breaking
10. In the stability of emulsion, which instability step is prevented by emulsifiers?:
A. breaking
B. coalescence
C. creaming
D. flocculation
11. An ‘emulsion within emulsion’ is designated as:
A. o/w/w
B. w/o/o
C. w/o/o/w
D. w/o/w
12. The main function of an emulsifier in the preparation of an emulsion is to:
A. develop a condensed membrane layer film
B. increase the repulsions between globules coming together
C. increase the surface free energy
D. reduce the interfacial tension
13. An emulsifier can be regarded as superior, if its mechanism of action is based on
the principle of:
A. developing solid adsorption film
B. forming monomolecular adsorption film
C. generating multimolecular adsorption film
D. increasing interfacial energy
14. An emulsifier is considered to be ideal, if it is soluble in:
A. aqueous, oil and gas phases
B. aqueous phase only
C. both aqueous and oil phase
D. oil phase only

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15. On commercial scale, emulsions are prepared by:
A. centrifugation
B. dialysis
C. freezing
D. homogenization
16. Microemulsion is NOT considered to be a true emulsion, because:
A. appearance is transparent
B. emulsifier is not used
C. immiscible phase is absent
D. internal phase is not spherical
17. A variety of factors would influence the rate of creaming in an emulsion.
The factor open to formulation pharmacist is to regulate:
A. density of dispersion medium
B. density of dispersed phase
C. globule size
D. volume of dispersion medium
18. Normally preservatives are added to an emulsion. One of the following
statements is true.
A. amount of the preservative added is below minimum inhibitory concentration
B. emulsifier should enhance the preservative action
C. preservatives remain in the aqueous phase
D. preservatives stay in the oil phase
19. For the formulation of w/o emulsion, the coalescence rate of:
A. w/o has no relationship to the type of emulsion formed
B. o/w is equal to w/o coalescence rate
C. o/w is greater than w/o coalescence rate
D. w/o is greater than the o/w coalescence rate
20. Auxiliary emulsifying agents are used to stabilize the emulsion. They act on the
principle:
A. adjusting the HLB value
B. strengthening the nonpolar tails of the emulsifier ^
C. strengthening the polar heads of the emulsifier
D. thickening the continuous phase
21. Emulsion have a ……… shelf life
A. short
B. no
C. large
D. none of the above
22. Creaming is a………. process
A. reversible
B. irreversible

10. GOURAV SINGH 9
C. A & B
D. difficult to predict
23. O/W emulsions normally cream ………
A. up first & down then
B. upward
C. downward
D. none of the above
24. Microemulsions contain globules of the size about ………
A. 10 micro meter
B. 1 micro meter
C. 0.1 micrometer
D. 0.01 micrometer
25. Downward creaming means …….. rate of sedimentation
A. negative
B. positive
C. same
D. no change
26. A mixture of span 20 and tween 20 forms……. type of emulsion
A. W/O
B. O/W
C. Milky
D. Hard
27. Density of oily phase increased by addition of …….
A. Butter
B. Coconut oil
C. water
D. brominated oils
28. Near CMC, micelles of the surfactant molecules assume the shape of
A. spherical
B. layered
C. rod shaped
D. cylindrical
29. Which one of the following emulsifier is used to stabilise the emulsion of W/O
type
A. SLS
B. Span 20
C. Tween 20
D. Tragacanth
30. Creaming in emulsion can be controlled by regulating
A. density of dispersed phase

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B. density of dispersion medium
C. globule size
D. volume of dispersion medium
31. An emulsifier is considered to be ideal, if it is soluble in
A. Aqueous phase
B. oily phase
C. Both A & B
D. none of the above
32. In the stability of emulsion, which important instability step should be prevented?
A. Breaking
B. Coalescence
C. Flocculation
D. Creaming
33. Emulsions made with tweens are
A. W/O
B. O/W
C. Clear
D. Unstable
34. The HLB system is used classify
A. Flavours
B. Colours
C. Surfactants
D. Perfumes
35. Emulsion containing more than two phases are called as
A. Mixed emulsion
B. Multiple emulsion
C. Complex emulsion
D. none of the above
36. Emulsion is
A. stable preparation
B. thermodynamically unstable preparation
C. biphasic system
D. Both B & C
37. Which of the following is/ are the theories of emulsification?
a. Monomolecular adsorption theory
b. Multimolecular adsorption theory
c. Solid Particle Adsorption theory
d. All of the above
38. Which of the following is not the cause of Instability in emulsion
a. Upward Creaming

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b. Phase inversion
c. Downward creaming
d. Mottling
39. Which of the following is a reversible phenomenon
a. Creaming
b. Coalescence
c. Breaking
d. All of the above
40. The phase inversion occur due to
a. changes in type of emulsifying agent
b. change in phase volume ratio.
c. Both a and b
d. None of the above
41. Which of the following is used as antioxidants for emulsified systems
a. Dodecyl gallate,
b. Butylated hydroxyanisole (BHT),
c. Butylated hydroxytoluene (BHT)
d. All of the above
42. Which of the following is identification test for emulsion
a. Dilution test
b. Cobalt Chloride Test
c. Conductivity Test
d. All of the above
43. When an emulsion is exposed to ultra-violet radiations. If the continuous
fluorescence is observed under microscope, then it is_____________ type emulsion.
a. w/o
b. o/w
c. microemulsion
d. Nano emulsion
44. Dry Gum Method is also known as
a. Continental method.
b. English method
c. Bottle method
d. Forbe’s method
45. In Dry gum method, 4:2:1 consist of
a. 4 parts oil, 2 parts water, and 1 part emulsifier
b. 4 parts water, 2 parts oil, and 1 part emulsifier
c. 4 parts emulsifier, 2 parts water, and 1 part emulsifier
d. 4 parts oil, 2 parts emulsifier and 1 part water

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46. The rheological property of emulsion can be controlled by
a. nature and concentration of emulsifying system
b. particle size of dispersed phase
c. viscosity of continuous phase
d. All of the above
47. The suspensions having particle size………………. are categorized as coarse
suspension.
a. Greater than ~1 mm
b. Greater than-10 mm
c. Both of the above
d. None of the above
48…………. exists when dispersed solid particles in a suspension retain change in
relation their adjoining liquid medium.
a. Surface area
b. Surface potential
c. Surface volume
d. None of the above
49. The equal distribution of all the ions in solution retain by……
a. Electric forces
b. Thermal motion
c. Both of the above
d. None of the above
50.The flocculated suspension is one in which zeta potential of particle is…… .
a. -05 to +05 mV
b. -10 to+10 mV
c. -20 to+20 mV
d. -30 to+30 mV
51……. determines the movement of charged particles via a liquid under the impact
of an applied potential difference.
a. Electrophoresis
b. Electrosmosis
c. Surface charge
d. Static movement
52………..is produced by forcing a liquid to course through a stationary solid phase.
a. Electrosmosis
b. Electrophoresis
c. The sediment potential
d. The streaming potential
53. The flocculated suspensions sediment………….
a. Slowly
b. Quickly

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c. More quickly
d. None of the above
54………..suspension involves individual particle settling.
a. Flocculated
b. Deflocculated
c. Both of the above
d. None of the above
55. Structured vehicles are also termed as or…………..
a. Thickening
b. Suspending agents
c. Both of the above
d. None of the above
56…….. is the concentration of globules at the top or bottom of the emulsion.
a. Creaming b. Cracking
c. Phase inversion d. State