MIXING Flashcards
1
Q
An operation used to change a non uniform system into a uniform one is known as
A
Mixing
2
Q
Our importance of mixing are
A
To produce a uniform distribution
To produce dispersion
To promote reactions
To improve organoleptic properties
3
Q
Three types of mixing are
A
Positive mixing
Neutral mixing
Negative mixing
4
Q
A mixture formed when two or more miscible liquids are mixed together by simple diffusion process is
A
Positive mixing
5
Q
Which type of mixing does not require energy
A
Positive mixing
6
Q
Type of mixture formed when insoluble solids are mixed with a vehicle to form a suspension or two immiscible liquids are mixed to form an emulsion is
A
Negative mixing
7
Q
Negative mixing requires
A
Continuous stirring
8
Q
Which type of mixture is static in their behavior
A
Neutral
9
Q
The type of mixture that it’s components does not have the tendency to mix spontaneously is known as
A
Negative mixing
10
Q
The type of mixture in which when it’s components are mixed they are hardly separated out is
A
Negative mixing
11
Q
Two equipments used in liquid mixing can be
A
Single -phase blending
Multi- phase mixing
12
Q
The type of liquid mixer that requires a low shear and high flow mixers to cause liquid engulfment is
A
Single -phase blending
13
Q
Which type of liquid mixer involves the mixing two or more miscible/ soluble liquids
A
Single -phase blending
14
Q
Single -phase blending requires the mixing of two or more… miscible liquids/immiscible liquids
A
Miscible liquids
15
Q
The type of liquid mixer that requires high shear and low mixer to create a droplets of one liquid in laminar, turbulent, transitional flow regimen depending on Reynolds number of flow is
A
Multi- phase mixing
16
Q
Which type of liquid mixer involves liquid that are not miscible
A
Multi phase mixer
17
Q
Single -phase and multi- phase mixing is an example of which mixer…
A
Liquid mixer
18
Q
Turbulent and transitional mixer uses …
A
Turbine and impellers
19
Q
Laminar mixing involves the use of…
A
Helical ribbon and anchor mixer
20
Q
Liquid mixing is performed with mixing element called
A
Rotational device
21
Q
The mixing element of liquid mixer must…
A
Produce necessary shear force and be in a suitable shape to act as an impeller to produce an appropriate pattern in the mixing vehicle
22
Q
Complete flow pattern depends on variations of
A
3 components in different parts of the vessel
23
Q
The 3 velocity components and flow pattern during mixing are
A
Radial flow/ vertical
Axial flow/ longitudinal
Tangential flow/ circular
24
Q
A satisfactory flow pattern depends on
A
The balance of the flow pattern
25
Flow pattern is influenced by
The form of impeller
The position of impeller
26
3 primary laws that governs flow characteristics are
Conservation of mass
Conservation of energy
Classic law of motion
27
A mass of fluid with whirling or circular motion that tends to form a cavity/ vacuum in the center of the circle is known as
Vortex formation
28
What is a strong circulatory flow pattern manifest into the forming of vortex near the impeller shaft
Vortex formation
29
Vortex is formed by placing shaft ...in the tank
Symmetrical
30
Blades in the turbine are arranged...to the center shaft to produce a vortex
Perpendicularly
31
1.It reduces mixing intensity by reducing the impeller velocity
2.Air bubbles in the fluid creates an uneven loading of the impeller blade
3.It causes oxidation
Is a disadvantage of ...
Vortex formation
32
Baffled container is used to prevent
Vortex formation
33
Vortex formation can be prevented by
Placing in an off central, inclined and side entering
Using baffle container
Using tank other than cylinderical tank
34
Baffle container introduced to prevent vortex formation converts tangential( circular )flow into...
Axial (vertical)flow
35
Axial flow or... tangential flow or ...radial flow or...
Longitudinal
Circular
Vertical
36
Inadequate longitudinal components causes liquid and solid to...
Rotate in layers without mixing
37
Baffle uses... flow system? Laminar/ turbulent/transitional
Turbulent flow system
38
Turbulent flow system can also be referred to as...
High viscous fluid or low viscous fluid
Low viscous fluid
39
Does laminar flow use baffle and why
Laminar flow system does not use baffle because it is a high viscous fluid
40
Liquid mixing can be divided into two which are
Mixing of liquid and liquid
Mixing of liquid and solid
41
Which type of liquid mixing involves mixing of two miscible and two immiscible liquids
Liquid and liquid mixing
42
Mixing of liquid and solid involves
Mixing of liquid and insoluble solids
Mixing of liquid and soluble solid
43
Mixing of two miscible liquids is an
Homogeneous mixture
44
Homogeneous or miscible mixture can occur only by simple diffusion which involves stirring and shaking T/F so it can be classified under what type of mixing
True
Positive mixing
45
During homogeneous mixture which type of flow system can be created
Turbulent flow system
46
...is the function of velocity gradient between two adjacent layers of a liquid
Turbulence
47
Vortex can occur due to ...kind of flow system
Turbulent flow system
48
Mixture of two immiscible liquids is also known as ...
Heterogeneous mixture
49
Emulsion is an example of...type of liquid mixture
Immiscible liquids/ heterogeneous mixtures
50
Ointment, powder,paste are example of...type of mixture
Positive mixture
51
When ...liquid is mixed in the presence of an emulsifying agent...is produced
Immiscible liquids
Emulsion
52
Mixing is efficient(continuous )for the production of ... emulsion
Stable/unstable or neutral emulsion
Stable
53
...is used for the blending of immiscible liquids
Turbine impeller
54
...creates a large enhancement in interfacial area thereby increasing the rate of mass transfer and rxn in blending of immiscible liquids
Turbine impeller
55
The type of turbine impeller needed for coarse dispersion is
Low shear hydrofoil design impellers
56
The type of impeller needed for effective fine emulsion is
Axial / radial flow impellers
57
The turbine impeller required for the production of stable emulsion is
High shear impeller
58
On a small scale ... is used for the preparation of emulsion
Mortar and pestle
59
Two stages of emulsion are
Primary and secondary emulsion
60
Which stage of emulsion involves the trituration of two immiscible liquids with an emulsifying agent
Primary stage
61
The dilution of the triturated immiscible liquids by the addition of more vehicle is ...stage of emulsion
Secondary stage
62
To produce a homogeneous emulsion, a coarse emulsion is passed through a...
Homogenizer
63
The mixture of liquid and soluble solids can be obtained by...
Stirring
64
Mixing of liquid and soluble solids is a ...change . Physical/chemical
Physical
65
Suspension is a ...
Heterogeneous mixture
66
Heterogeneous mixture are unstable T/F
T
67
The ingredients of ...type of mixture separate when allowed to stand
Heterogeneous mixture/Suspension/negative mixture
68
A suspension agent is required in mixing of liquid and immiscible solid to produce...stable/ unstable suspension
Stable suspension
69
On a small scale suspension can be produced using...
Mortar and pestle
70
The mixture of two immiscible liquids yields...,the mixture of liquid and insoluble solids yields...,the mixture of liquid and soluble solid gives a ...
Emulsion
Suspension
Solution
71
The mixture of two miscible liquids yields a ...
Solution
72
The type of impeller for suspension is
Axial flow impellers
73
Physical distribution and dispersion of gas in liquid is type...of liquid and gas mixing
Type 1
74
Application of type 1 liquid and gas mixing is limited to
Foam and froth derivation
75
Liquid gas mixing type 2 involves
Mass transfer process eg. Absorption,stripping,chlorination and oxidation
76
...type of impeller is preferred in liquid gas mixing
Radial flow impeller
77
The most suitable type of impeller for liquid gas mixing is
Disk turbine impellers
78
Special type of mixing eg hydrogen gas is expensive, hazardous and critical. T/ F
T
79
List 3 factors liquid mixing are
Material related factor
Equipment related factor
Process related factor
80
Three type of liquid mixing are
Liquid liquid mixing
Liquid solid mixing
Liquid gas mixing
81
Physical properties eg. Density, viscosity, miscibility can be seen under ,..type of factor affecting liquid mixing
Material related factor
82
Shape of impeller, position of impeller,cost and maintenance,presence or absence of baffle,shape and size of container is under which factor that affects liquid mixing
Equipment related factor
83
Speed of rotation,time required for mixing,amt of power or energy,ease of operation and batch size is under which factor affecting liquid mixing
Process related factor
84
4 liquid mixing mechanism are
Bulk transport
Turbulent flow
Laminar flow and
Molecular diffusion
85
Which type of blade are used in bulk transport
Rotating blade
Paddle
86
Turbulent mixing is characterized by
Random fluctuation
87
Highly viscous fluid is encountered in ... mixing
Laminar
88
Another name for solid solid mixing is
Powder mixing
89
Solid solid mixing is a ...type of mixture
Neutral mixture
90
Solids are divided into
1.cohesive material
2.noncohensive material
91
Another name for noncohesive material is
Flowable material
92
Cohesive material are characterized by its
Resistance to flow through an opening
93
... type of solid solid mixing is difficult due to formation of lump and aggregate
Cohesive eg. Wet kaolin
94
Grain,plastic chip,sand is an example of
Solid solid mixing (noncohesive)
95
4 mechanism for solid solid mixing
Shear mixing
Convection mixing
Diffusive mixing and
Combined mechanism
96
Connective mixing is also known as
Macro mixing
97
Combined mechanism is also known as
Diffusive mixing
98
Diffusive mixing is known as ....
Micromixing
99
The sliding of particles in plane over each other is
Shear mixing
100
Shear mixing is created within the mass of material by using...
Agitator arm or a blast of air
101
The mixing that produces small scale uniformity on local basis is
Shear mixing eg. Intensifiers, speed chopper blades
102
Factors that influences solid mixing include
Nature of material
Particle size
Material density and
Amount of material to be mixed
103
The mixing of insoluble powder and liquid is
Semi-solids
104
Solids can be suspended in liquid by the use of the ...in cylinderical container
Flat bladed turbine
105
The mechanism in mixing semi solids depends on the ...which show variation
Character of the material
106
5 theories of mixing of semi solid are
Pellet and powder state
Pellet state
Plastic state
Sticky state
Liquid and fluid state
107
Which state is obtain when making a pill mass
Plastic state
108
Which state is aimed at moisturizing powder for tablet granulation
Pellet state
109
In which state of semi solid is homogenization low
Pellet and powder state
Pellet state
Sticky state
110
In which state is homogenization rapidly achieved
Plastic state
111
Emulsion can be reduced by the use of... suspending agent
Thioxotropic
112
...are natural mixture with no tendency to segregate although sedimentation may occur with suspension in fluid media and emulsion may separate
Semi solid
113
Emulsion may be evaluated by
Globular count/ globule rise distribution
114
The addition of liquid to bulk of dry powder causes solid to ball up and form...
Small pellet
115
The cushioning effect of pellet embedded in a matrix of dry powder makes the pellet difficult to break up T/F
T
116
The conversion of more dry powder to pellets until all material is in the state is in my hich state...
Pellet state
117
Which state in semi solid mixing is characterized with coarse granular appearance and there's no coherence and agitation that will cause the pellet to break into small granules
Pellet state
118
In which state is the granular appearance lost and there's an adherence of aggregate material
Plastic state
119
In which state is the semi solid appearance is paste like and the surface is shiny
Sticky state
120
The addition of water that results in the decrease of consistency until the mixture flows under its own weight and drains off vertically the surface is which state of semi solid
Liquid state
121
1.Production of complete blend to avoid product damage
2.dust-tight
3.low maintenance and power consumption
Are characteristics of..
Ideal mixer
122
Mixing device based on shape and pitch is
Propeller
Turbine
Paddle
123
Propeller, turbine and paddle is known as
Impeller
124
Axial flow impellers makes an angle less than 90° T/F
True
125
Axial flow is ...to impeller shaft
Parallel
126
Axial flow is commonly used for...type of flow
Turbulent and transitional flow
127
In axial flow impellers, impellers are mounted at the ...of the baffled vessel.
Center
128
Radial flow is...to the axis of impeller
Parallel
129
Radial flow is used for... mixing application
Single and multi-phase mixing
130
Radial flow impellers is effective for... mixing
Gas liquid mixing and liquid liquid mixing
131
Commonly used radial flow impellers are
Rushton turbine
Bar turbine
Open blade turbine
132
Radial flow impellers are produced by
Flat blade turbine
133
Propeller mixer consist of how many blade design
Three
134
Propeller mixer is commonly used for liquids with... movement
Longitudinal movement
135
Propeller mixer rotates at ...speed at ...rpm
High
8000rpm
136
The widely used form of mixer for liquid of low viscous is
Propeller mixer
137
...mixer cannot be used for high shear
Propeller mixer
138
Propeller mixer is ineffective with viscosity greater than...Ns/m3
5Ns/m3
139
The type of mixer that consist of circular disk is ...
Turbine mixer
140
Straight/curved blades are found in ... mixer
Turbine mixer
141
Turbine mixer rotates at... speed of...rpm
Low
50-200rpm
142
Flat blade turbine produces ...type of flow
Radial and tangential flow
143
Pitched blade turbine produces...flow
Axial flow
144
Great shearing force
Effective for high viscous solution of 9ns/m3
Suitable for emulsification
Is an advantages of...mixer
Turbine mixer
145
...mixer consists of a central hub with long flat blades attached vertically
Paddle mixer
146
Paddle mixer are...in shape and have... surface area
Pitched ,dished , hemispherical
Large
147
They rotate at ... speed of...rpm
Low
100 rpm
148
An alternate design for viscous range of liquid is ...
Planetary motion mixer
149
Vortex formation is not possible with...type of mixer
Paddle impeller
150
Advantage of paddle mixer is
Low speed mixing that produces no vortex formation
151
Disadvantages of paddle mixer is
It's suspension mixing is poor and baffle tanks are required
152
...mixer have limited use in industry
Shaker mixer
153
Application of intense vibration causes emulsification in
Sonic and ultra sonic mixer
154
The break of liquid into globule by ultrasonic mixer is known as
Cavitation method
155
Sonic mixer uses a large scale emulsification called...for mixing of immiscible liquid
Rapisonic homogenizer
156
...type of mixer can be used for batch process
Sonic mixer
157
...mixer is suitable for thermolabile substances and useful for low viscous fluid
Ultrasonic/sonic mixer
158
...mixer produces intense shearing force and turbulence by the use of high speed rotors
Siverson mixer
159
Siverson mixer makes use of ...for the breakdown of dispersed liquid into small globule
Circulation
160
...mixer is used for the preparation of emulsion and cream of fine particle size
Siverson mixer
161
Siverson mixer uses... operation
Batch and continuous operation
162
Clogging of mesh pore is a disadvantage of... mixer
Siverson mixer
163
Three mixers for semi solids are
1. Beater and kneader
2. Mixer extruder
3. Shear mixer
164
Another name for shear mixer is...
Mixing roll
165
Examples of beater and kneader is ...
Sigma and planetary mixer
166
Another name for beater and kneader is
Agitator mixer
167
Examples of mixer extruder is
Roto feed mixer
168
Examples of mixing roll is
Colloidal and triple roller mill
169
Advantage of beater and kneader mixer is
The shape and it's movement is cleared from all sides and it avoids dead spot
170
Disadvantages of sigma is
The entertainment of air
171
...type of mixer is used for wet granulation processing tablets, and ointments
Beater
172
...type of mixing reduces viscosity by heating and heat dissipation
Beater mixer
173
It operates at fixed speed is a disadvantage of which mixer...
Beater
174
...type of semi solid mixer uses shear mechanism
Planetary mixer
175
Planetary mixer uses basic operation of mixing and blending to produce... shear granules
Low
176
Planetary mixer work in fixed speed
T/F
False
It works at varying speed
177
...type of mixer is the most useful in wet granulation
Planetary mixer
178
Planetary mixer is limited to only .
Batch work
179
Mixer extruder depends on
Cutting
Folding of material
180
Mixing of materials that are difficult to mix eg. Clays and thermoplastic is an advantage of...type of semisolid mixer
Mixer extruder
181
Two types of shear mixer is
Colloidal mill and
Triple roller
182
The type of shear mixer that breakdown agglomerate of emulsion to produce droplets is...
Colloidal mill
183
What's the advantages of colloidal mill
Fine particle distribution through optimal shear force
High capacity with minimal space requirements
184
Unlimited application due to high flexible homogenization system is a characteristic of...
Colloidal mill
185
Triple roller mill is composed of
Hard abrasion-resistant material
186
Triple roller mill produces ...
Uniform dispersion
187
Triple roller mill is suitable for continuous processes . T/F
T
188
Four conditions required for powder mixing is
Mixing volume
Mixing mechanism
Mixing time
Handling mixed powder
189
Classifications of equipments for solid mixing is based on
Flow properties
Mixing scale
190
Classifications based on flow properties is
Free-flow solids (v-cone blender, double conc.n vertical screw mixer)
Cohesive solid (sigma & planetary mixer)
191
Classifications of solid mixing based on mixing scale is
Batch type(small scale)
Continuous type (large scale)
192
Examples of batch type is
Mortar and pestle, V.cone blade, double conc mixer, ribbon blender, sigma mixer, planetary paddle, fluidized mixer
193
Examples of continuous type is
Barrel type
Zig-zag type
194
The most common used mixers
Agitator mixer
Tumbling mixer
195
...is a prerequisites for manufacturing all solid dosage forms which involves powder mixing and is used in uniformity of content
Optimum mixing
196
Tumbler mixer, agitator mixer, double conc. mixer, v-blender,silo mixer, gravity silo mixer, mechanical silo mixer,flow mixer ,twin shaft paddle, pneumatic mixer is a type ...mixer
Solid -solid mixers
197
Buffer is used for both wet and dry mixing in solid solid mixer. T/F
True
198
All the contact part is made up of....
Stainless steel
199
Mixing occur due to... tumbling motion
Tumbling motion
200
Double conc.mixer is efficient for mixing...n ..
Dry powder and granulated homogeneous
201
Double conc mixer is used for small amount of powder of different densities.T/F
True
202
Twin she'll blender or v cone blender is ..shape that uses ...
Stainless steel
Transparent plastic
203
V-blender is used for
Dry mixing
204
The process when a system contains particle with different size and densities that preferentially or accumulate into one area over another is ...
Segregation and de-mixing
205
Segregation can be prevented by
Minimizing physical difference
Increasing cohesiveness of formulation
Optimizing blending conditions
206
Mechanism for segregation are
Sifting segregation
Fluidization segregation
Air current
Angle of repose
Chute trajectory
207
For mixing powders with small qty of liquid where the constituent is cohesive/sticky the material agglomerate into balls. Which type of mixer will be suitable for such mixer
Agitation mixer
208
The type of mixer required for the agglomeration of desired food and pharmaceutical is
Tumbling mixer
209
Choosing right equipment discourages cross contamination,dust formation and aggregation. T)F
True
