Lab Assessed

Question 1

Explain why the concept of ‘intermolecular forces’ is relevant to pharmaceutical practice

Answer 1

Intermolecular forces are the forces which mediate interaction between molecules, including forces of attraction or repulsion

Important for understanding and achieving stable formulations that will act in a reproducible manner on the body

Question 2

Describe repulsive forces

Answer 2

All molecules have an electron cloud. When such molecules are brought closer together (decreasing intermolecular distance), these like-charged cloud repel (repulsion)

Question 3

Identify 3 common types of attractive forces and state whether or not they are stronger or weaker than covalent, ionic or metallic bonding

Answer 3

• Ion-dipole
• van der Waal’s (dipole-dipole and London dispersion)
• Hydrogen bonding

Intermolecular forces of attraction are weaker than intramolecular forces of attraction so they are weaker.

Question 4

Explain the effect temperature and pressure exert on gas molecules

Answer 4

Increasing temperature increases the amount of energy in the system, causing the gaseous molecules to move at a greater speed.

Increasing pressure increases the number of molecular collisions on the walls of the container.

Question 5

Identify and explain the two parameters that can be adjusted to cause the liquefaction of gas

Answer 5

Decreasing temperature decreases kinetic energy causing the gaseous molecules to move slower.

Increasing pressure results in the molecules becoming closer together.

By adjusting these two parameters in such a way, the attractive forces of the gas molecules can bring them together to condense into a liquid.

Question 6

Explain the significance of critical temperature and critical pressure.

Answer 6

Critical temperature is the temperature above which the liquid state can no longer exist

Critical pressure is the pressure required to liquefy gas (assuming critical temperature)

Both critical temperature and critical pressure make up the critical point.

Question 7

Define vapour pressure and discuss how different vapour pressures affect equilibrium

Answer 7

Vapour pressure is the pressure exerted by molecules that have evaporated.

When the actual vapour pressure (P) is below the equilibrium vapour pressure (Peq), the liquid will evaporate to shift towards equilibrium.

When P = Peq, there is an equal amount of evaporation and condensation (note: the system is not static)

When P > Peq, molecules in a gaseous state condense into a liquid state to decrease the vapour pressure to shift towards equilibrium.

Question 8

Identify and define the two types of solids

Answer 8

Crystalline - solids that are structurally ordered forming a crystal lattice

Amorphous - solids without order

Question 9

Compare and contrast crystalline and amorphous solids with reference to:

• Geometry
• Melting point
• Latent heat of fusion
• Directional properties

Answer 9

Geometry - crystalline solids have defined shape and symmetry

Melting Point - crystalline solids have defined melting points whereas amorphous solids tend to melt over a range of temperatures

Latent Heat of Fusion - Fixed for crystalline solids, not for amorphous solids

Directional Properties - crystalline solids are anisotropic, amorphous solids are isotropic

Question 10

Explain the concept of ‘liquid crystals’

Answer 10

Liquid crystals are systems in which there is some degree of molecular order while maintaining an overall fluid state (e.g. lipid bilayer)

Question 11

Explain the concept of ‘birefringence’ and state which types of substances are most likely to have it

Answer 11

Birefringence is an optical property in which a single ray of polarised light entering an anisotropic material is split into two rays, travelling at different speeds and different directions.

Crystalline substances have different concentrations of atoms along different axes (anisotropic) and can exhibit birefringence.

Question 12

Identify and explain the state change that occurs when the temperature is changed and pressure is lower than the triple point

Answer 12

When temperature changes and pressure is lower than the triple point, sublimation occurs. Sublimination is the state change from solid to a gas without first changing to liquid

Question 13

Explain the different components of the phase rule (F = C-P+2)

Answer 13

F = degrees of freedom: the number of variables that must be fixed to define a system.

C = number of components: a distinct chemical species in a system.

P = number of phases present: a physically distinct portion of a system separated by boundaries.

Question 14

Explain the differences in degrees of freedom when finding a point vs. a line

Answer 14

When finding a point, we need two degrees of freedom. In other words, we need two variables to be fixed (pressure and temperature).

When finding a line, we need one degree of freedom. This means that we need one fixed variable (pressure OR temperature).

Question 15

State the number of components and phases present in a solution of alcohol+water vs. ice+water

Answer 15

Alcohol+water = 2 components, 2 phases

Ice+water = 1 component, 2 phases

Question 16

Describe the graph appearance of a two-component system containing liquid phases and a two-component system containing solid and liquid phases.

Answer 16

Two-component liquid phases: A parabolic curve that defines conditions whereby a single liquid phase or two-liquid phase exists. The closer the two liquids are to a 50:50 ratio, the greater the temperature needed to produce a single liquid (miscible) phase.

Two-component solid-liquid phase: separated into a solid phase and a liquid phase. In the liquid phase, a declining curve that intersects an increasing curve. The more disproportional the ratio of solids are, the greater the temperature needed to produce a single liquid phase.

Question 17

Describe the ‘eutectic point’

Answer 17

The lowest temperature at which liquid can exist in a two-component system containing solid and liquid

Question 18

Describe the appearance of a three-component diagram

Answer 18

Triangle with each corner designated to the 100% component of one substance and 0% component of another substance.

Question 19

Define ‘supercritical fluids’

Answer 19

State generated when pressure and temperature exceed the critical point. The resulting product has liquid-like density and gas-like viscosity and diffusivity.

Question 20

Define a polymorph

Answer 20

A compound that can crystallise in different forms

Question 21

Define a solvate/hydrate

Answer 21

A compound formed by the interaction of a solvent and a solute.

Question 22

Describe what is meant when a material is called ‘lyotropic’

Answer 22

A material is lyotropic when it forms liquid crystal phases upon the addition of a solvent.

Question 23

Describe the difference between anisotropy and isotropy

Answer 23

Anisotropy - a difference in chemical property when measured along difference axes

Isotropy - the physical properties are identical in all directions

Question 24

Assess the differences in properties between crystalline and amorphous substances

Answer 24

Crystalline:

• sharp melting point
• low solubility
• low dissolution rate
• low bioavailability
• high stability

Amorphous:

• broad melting point
• high solubility
• high dissolution rate
• high bioavailability
• low stability

Question 25

Define 'polymorphism' and discuss the chemical and physical differences in polymorphs

Answer 25

Polymorphism - the ability of a solid compound to exist in more than one crystal lattice. Polymorphs are chemically identical but have varying physical properties (solubility, melting point, dissolution rate, density, chemical and physical stability, hygroscopicity, etc.).

Question 26

Describe what is meant by an 'interface' and explain the difference between a surface and an interface

Answer 26

An interface is a boundary between two immiscible phases. A surface can only exist with phase boundaries involving gas (e.g. gas-solid, gas-liquid)

Question 27

Explain the significance of interfaces on pharmaceutics

Answer 27

Formulation stability | Permeation process

Question 28

Discuss the differences between cohesive forces and adhesive forces

Answer 28

Cohesive forces - forces of attraction between molecules of the same phase Adhesive forces - forces of attraction between molecules of one phase with molecules of another phase.

Question 29

Explain how surface tension is produced

Answer 29

Surface tension can be produced in vapour-liquid interfaces. This is because the surface liquid molecules have cohesive forces existing between other molecules either adjacent or below (bulk liquid molecules have cohesive forces in all directions). As a result, there is a net inward pulling force pulling towards the bulk, causing the liquid surface to contract, leading to surface tension.

Question 30

Explain the Du Noüy Ring Method measures

Answer 30

The force necessary to detach a platinum-iridium ring immersed at the surface or interface is proportional to the surface or interfacial tension, respectively

Question 31

Define 'surfactant'

Answer 31

Surfactants are compounds that lower the surface tension between two liquids, a liquid-gas, or between liquid-solid by interacting with both phases of a system (possessing lipophilic and hydrophilic components)

Question 32

Describe the orientation of surfactant molecules at a water-air surface

Answer 32

Polar heads facing the liquid phase and non-polar tails facing the vapour phase. Surfactant molecules at low concentrations can dissolve in water (due to polar component), however, at a certain concentration the molecules will 'line up' at the water-air surface and orient themselves in such way (i.e. saturation).

Question 33

Describe 'micelles'

Answer 33

Micelles are structures composed of surfactant molecules and are formed by increasing the surfactant concentration beyond the CMC point. Micelles can hold oils in water and water in oils depending on the orientation of the surfactant molecules (lipophilic inside, hydrophilic outside or hydrophilic inside, lipophilic outside respectively).

Question 34

Discuss changes in surface tension, surfactant activity and micelle formation when surfactant concentration is increased

Answer 34

1. ) Surface tension remains constant - surfactant molecules present in the solution are relatively soluble and exist within the solution. Surfactant may line up at the surface, however, it is not enough to cause an effect on the surface tension. 2. ) Surface tension decreases - once concentration of surfactant increases, water begins to interact more strongly with the lipophilic tails causing surfactant to line up at surface, surface tension begins decreasing to the CMC point. 3. ) Surface tension plateaus - beyond the CMC point, an increase in surfactant concentration will see the formation of micelles as surface has been saturated.

Question 35

Compare and contrast surfactants in water-air vs. in two immiscible liquids

Answer 35

In both water-air and liquid-liquid and at above a concentration, surfactant molecules will begin lining up at the surface to reduce surface tension. However, as micelles form in the water in a water-air system, in the liquid-liquid system micelles form in both. Furthermore, the micelles in each of the two liquids will be structured differently, one with hydrophilic heads on the outside and the other with lipophilic tails on the outside instead.

Question 36

Discuss the applications of surfactants

Answer 36

Since many drugs are lipophilic, and oral liquids tend to be aqueous, surfactants allow drugs to reside in aqueous solutions. Without surfactants, lipophilic drugs are prone to aggregating (clumping) and produce air pockets. Therefore, surfactants act as a coating over the drug which prevents the molecules from interacting (i.e. clumping).

Question 37

What is HLB

Answer 37

HLB stands for 'hydrophilic-lipophilic balance' and is the measure of how hydrophilic or lipophilic a surfactant is High HLB = high water solubility Low HLB = high fat solubility

Question 38

In the HLB equation... rHLB = (HLB(a) x a) + (HLB(b) x b ...'a' and 'b' represent what? a. ) amount of each surfactant b. ) concentration of each surfactant c. ) proportion of each surfactant d. ) surfactant constant

Answer 38

c.) proportion of each surfactant (adding to 1)

Question 39

Define a 'tablet'

Answer 39

A compressed solid dosage form that contains drugs with or without excipients

Question 40

State the advantages of tablets

Answer 40

- Precise dose - Easy to use (everyone knows how to use it) - Convenient to carry - Large scale manufacturers (machines can mass produce tablets easily) - Low cost of excipients - Taste masking - Complex designs possible - High stability (solid - does not diffuse, evaporate, easier to store)

Question 41

State the disadvantages of tablets

Answer 41

- Difficult to swallow (children, elderly, patients with conditions interfering with swallowing) - Limited dose flexibility (1 tablet, half a tablet but can't administer e.g. 1/5 a tablet) - Difficult to compress some drugs (e.g. amorphous) - Special packaging required (e.g. hygroscopic or oxygen sensitive drugs) - Bioavailability issues (dissolution necessary)

Question 42

Explain the process of tablet compression

Answer 42

- Drug powder is placed in a *hopper* which is connected to a feed tube - Feed tube releases small amounts of powder to the die - The upper punch will then compress the powder into a tablet

Question 43

State when ideal flow and compression properties are seen in particles

Answer 43

When particles are sized 0.2-0.5 mm

Question 44

Identify the THREE types of tablet compression

Answer 44

- Direction compression - Dry granulation - Wet granulation

Question 45

Explain direct compression (include advantages and disadvantages)

Answer 45

Direct compression is the cheapest and fastest method of tablet compression. It involves taking the powder mix and compressing it directly. Another advantage is that is can be used for moisture- and heat-sensitive drugs. Disadvantages include a heterogenous powder mixture, limited drug concentration and a weak tablet.

Question 46

Explain granulation

Answer 46

Granulation is the process of narrowing the particle size range (to increase flowability) by forming granules prior to compression. Granulation provides a tablet with a homogenous powder mixture capable of high drug concentrations.

Question 47

Discuss under which circumstances would dry vs. wet granulation be appropriate

Answer 47

Dry granulation has an 'intermediate' cost and speed whereas wet granulation is expensive and slow. For moisture- and heat-sensitive drugs, we would need to use dry granulation. This is because wet granulation involves wetting and then heating the drugs which some drugs cannot undergo. However, to achieve the 'strongest' tablet, wet granulation is used.

Question 48

Explain the purpose of a 'diluent' and provide an example

Answer 48

Diluents are fillers used when the dosage itself is inadequate to produce an entire bulk tablet. It can also reduced irritation and is usually clean, cheap, non-toxic, non-reactive, aesthetic, and compressible. Example: starch, lactose

Question 49

Explain the purpose of a 'binders and adhesives' and provide an example

Answer 49

Binders and adhesives ensure that the tablet stays intact (i.e. acts as a glue). Example: acacia

Question 50

Explain the purpose of a 'lubricants and glidants' and provide an example

Answer 50

Lubricants prevent the tablet from adhering to surfaces (especially the die/punches) and improve the powder/granule flow. Glidants prevent friction between particles to improve powder/granule flow. Example (both): talc

Question 51

Explain the purpose of a 'disintegrants' and provide an example

Answer 51

Disintegrants ensure that tablets will break down once it is in contact with water or aqueous fluids in the GIT. Example: starch

Question 52

Explain the purpose of a 'tablet coating' and provide an example

Answer 52

Tablet coatings are added to protect tablet contents and/or protect the body from the tablet. Additionally, they can also be used to make the tablet easier to swallow (aesthetics, flavouring).

Question 53

Explain the purpose of a 'flavouring agent' and provide an example

Answer 53

Flavouring agents are used to mask the taste of certain drugs. This is especially important in tablets that dissolve before swallowing.

Question 54

Identify the different types of tablets

Answer 54

- Orally ingested - Used in oral cavity - Non-oral - Prepare solutions

Question 55

Discuss, under which circumstances, would standard or multiple compressed orally-ingested tablets be appropriate.

Answer 55

Single compression is simple and fast but is unable to combine multiple actives in a single tablet. Multiple compression allows for the compressive of actives in different layers, subsequently combining them in a single tablet. Single compression is preferred when a tablet only has one active component. However, multiple compression is preferred when multiple active components are present in a single tablet.

Question 56

Describe delayed release tablets and state what excipients are needed to make them.

Answer 56

Delayed release tablets are two layer tablets where the external layer releases drug immediately while the internal layer releases drug slowly. An enteric coating can be used to ensure that a drug is not released until it reaches a specific part in the GI tract.

Question 57

Explain when it may be appropriate to administer chewable tablets and state what property must be considered.

Answer 57

Chewable tablets may be administered to children who have difficulty swallowing normal tablets. Since tablets are being chewed, it is important to consider the flavouring to ensure palatability.

Question 58

Explain why it is important to test raw materials before they are made into a tablet and give examples of what methods we may use to do so.

Answer 58

Because we must ensure that the active ingredient and the excipients are pure. Example: melting point, thin-layer chromatography, IR, MS

Question 59

State the three different ways a tablet can 'break'

Answer 59

- Capping (partial/full removal of crown of tablet) - Lamination (breakdown of layers) - Cracking/chipping (cracks)

Question 60

Discuss why testing tablet 'hardness' is important, and include the approximate range of force that a typical tablet can endure. (Extra: discuss if we should expect chewable and sustained release tablets to have more or less force endurance)

Answer 60

Tablets can be exposed to mechanical shock during manufacturing, packaging, transport or handling. 4-10 kg/cm2 Since chewable tablets need to be chewed and relatively easy to breakdown, it should have lower force limit (3 kg/cm2). Sustained release tablets are made to remain intact in harsher conditions, so we can expect a greater force limit (10-20 kg/cm2).

Question 61

Discuss the difference between tablet hardness and tablet friability

Answer 61

Hardness is the amount of force required to break a tablet whereas friability is the tendency of a table to chip/crumble. A highly friable tablet is more prone to chipping.

Question 62

Weight variation is a parameter used to assess tablet quality. Explain how this is done.

Answer 62

Determining weight variation can help establish tablet consistency. This can be done by weighing 20 tablets individually and calculating the average weight. In order for a set of tablets to be considered consistent, there must be a deviation of no more than 20%.

Question 63

Mechanical strength and weight variation are two parameters used to measure tablet quality. Identify five other methods.

Answer 63

- Visual defects - Content uniformity - Disintegration - Dissolution - Stability testing

Question 64

Describe how reactions occur and state the factors affective rates of reaction.

Answer 64

Reactions occur when molecules collide with each other with sufficient energy and the correct orientation. Factors: - Temperature - Light - Catalyst - Concentration

Question 65

Describe unimolecular reactions

Answer 65

Unimolecular reactions are reactions that involve a change in only one molecule. This can result in: - one molecule decomposing into two or more atoms/molecules - one molecule isomerising into a molecule with a different structure

Question 66

Describe bimolecular reactions

Answer 66

Reactions that involve two molecules that can: - associate (A + B → AB) - exchange (A + B → C + D)

Question 67

Reaction rate is given by the expression dc/dt. Describe what dc/dt means.

Answer 67

The decrease of concentration over a (extremely small) time interval.

Question 68

State the integrated rate laws of zeroth, first and second order reactions

Answer 68

Zero: [A] = [A]0 - kt First: ln[A] = ln[A]0 - kt Second: 1/[A] = 1/[A]0 + kt

Question 69

State the half-life equations of zeroth, first and second order reactions

Answer 69

Zero: t(1/2) = [A]0/2k First: t(1/2) = 0.693/k Second: t(1/2) = 1/k[A]0

Question 70

When the concentration of one reactant is much greater than the other, what order reaction is it classified as, and what is the assumption we make?

Answer 70

Pseudo-order reaction. Assumption: that concentration change in the greater reactant is negligible and hence, we treat the reaction as a first-order reaction.

Question 71

Explain how an increase in temperature increases rate of reaction.

Answer 71

At higher temperatures, reactant molecules have more kinetic energy, move faster, and collide more often with greater energy

Question 72

State the Arrhenius equation

Answer 72

k = Ae^(-Ea/RT)

Question 73

Explain how concentration of reactants affect rate of reaction.

Answer 73

As the concentration of reactants increase, so does the likelihood of the reactant molecules colliding Kinetic-molecular theory: states that the number of collisions per second depends on the number of particles per litre (i.e. concentration)

Question 74

Explain how solvents affect rate of reaction

Answer 74

Neutral molecules: use solvents that have similar polarity to the reactant (e.g. polarity of reactant < product, use low polar solvent) Ionic molecules: use similarly charged solvent to reactant to increase reaction rate.

Question 75

Explain how catalysts affect rates of reaction

Answer 75

Catalysts speed up reactions by changing the mechanisms. This is done by decreasing the activation energy by providing an 'alternate pathway'. Catalysts are not consumed in the reaction and only a small quantity is needed to affect the rate of reaction of a large reactant.

Question 76

State the two types of catalysts

Answer 76

Heterogenous - catalyst and reactants form separate phases (e.g. solid in liquid mixture). Homogenous - catalyst and reactants are in the same phase.

Question 77

State the 4 processes that affect stability

Answer 77

- Hydrolysis - Oxidation - Isomerisation - Photolysis

Question 78

State 4 environmental factors that affect stability

Answer 78

- Heat - Oxygen - Moisture content - Light

Question 79

Define hydrolysis and explain how it can be prevented in drugs.

Answer 79

Hydrolysis is the chemical breakdown of a compound due to reactions with water. Prevention: - Use buffers to prevent pH based hydrolysis - Adding desiccants (substance that absorb water) - Changing formulation - Modifying solubility

Question 80

Which functional groups are more prone to hydrolysis?

Answer 80

Ester and amides.

Question 81

Define oxidation and state one factor affecting the rate of oxidation.

Answer 81

A reaction with oxygen to produce an electronegative molecule (either through removal of positive atom or electron or additional of electronegative atom). Factors affecting: - temperature (increases) - fatty acids (increases) - state of compound - degree of (un)saturation - dilution (decreases rate)

Question 82

Provide a method to reduce oxidation.

Answer 82

- Air-tight packaging to prevent oxygen contacting product - Include antioxidants (e.g. ascorbic acid) - Include reducing agent

Question 83

Define isomerisation

Answer 83

The conversion of an active drug into a less active state

Question 84

Explain photolysis and state a method of preventing photolysis.

Answer 84

Photolysis is the decomposition of molecules by light. Molecules can absorb light and become excited. This must occur at the right frequency. The energy absorbed by the molecules may be sufficient to reach activation energy and cause degradation or reactions with other components. Photolysis can be prevented by packaging compounds in bottles made with special brown glass to protect from light.

Question 85

Describe hard capsules

Answer 85

Solid dosage forms comprising of a physiologically inert hard exterior shell filled with therapeutic substance

Question 86

State 4 methods of quality testing hard capsules

Answer 86

Disintegration Dissolution Content uniformity Weight variation

Question 87

Describe what is meant by 'bloom strength'

Answer 87

Bloom strength is the measurement of the strength of a gel (i.e. the amount of force needed to penetrate the surface of gelatin)

Question 88

Desiccants are often found in capsule bottles. Explain why.

Answer 88

Hardshell capsules need to have a moderate amount of water. When the moisture content is below 12%, the capsule can be too brittle. On the other hand, capsules with a moisture content above 18% can be too soft. Hence, it is important to manage the levels, and therefore, the intake/release of moisture.

Question 89

Describe soft gels (soft capsules)

Answer 89

Are one-piece hermetically sealed soft shells

Question 90

State the advantages of soft gels

Answer 90

- Can incorporate oily drugs in liquid form - Size and shape flexibility - Accurate dosing of low concentration drugs - Manufacturing process devoid of particulates

Question 91

State the disadvantages of soft gels

Answer 91

- Containing interior liquid makes capsules less stable - Difficult to incorporate water soluble drugs - Tough to extract contained drug for compounding

Question 92

State the advantages of hard shell capsules

Answer 92

- Offer advantages of tablet coating - Can co-formulate incompatible substances - Can incorporate drug as powder or granules - Can readily retrieve drug for extemporaneous compounding

Question 93

State the advantages of tablets

Answer 93

- Rapid large scale manufacturer - Low-cost manufacture - Complex designs possible - Can be halved if uncoated/non-specialised

Question 94

State 3 unofficial tests for tablets

Answer 94

- General appearance - Uniformity of diameter and thickness - Resistance to crushing (hardness)

Question 95

Explain the hardness test

Answer 95

The test measures the strength of the tablet to withstand the pressure applied. Hardness can affect the disintegration and friability.

Question 96

State the 5 official tests for tablets

Answer 96

- Uniformity of weight - Friability - Disintegration - Content uniformity (assay) - Dissolution

Question 97

Uniformity of weight is an official method of quality testing tablets. Explain how it is conducted.

Answer 97

By taking 20 tablets and weighing them individually. Calculate the average and compare this value to each tablet. No more than 2 tablets should deviate by more than a certain percentage. and non should deviate by twice that percentage.

Question 98

Friability is an official method of quality testing tablets. Explain how it is conducted.

Answer 98

The test measures the ability of the tablet to withstand abrasion after a tumbling motion (using friabilator). The maximum weight loss acceptable is <1%. If above 1%, repeat twice and take the mean of the 3 measurements. Tablets that are cracked or broken fail the test.

Question 99

Disintegration is an official method of quality testing tablets. Explain how it is conducted.

Answer 99

Measuring the breakdown of a dosage form. Test is conducted with 6 tablets immersed in water at a certain temperature and is given a specified amount of time to disintegrate completely. Failure to disintegrate within this time will call for 12 additional tablets to be tested.

Question 100

Assay (uniformity of content) is an official method of quality testing tablets. Explain how it is conducted.

Answer 100

The test of the determination of the amount of an active ingredient in a drug product.

Question 101

State the 4 methods of measuring the surface tension

Answer 101

- Du Nuoy Ring Method - Sessile Drop Method - Capillary Rise Method - Wilhelmy Plate Method

Question 102

Explain the Sessile Drop method

Answer 102

A droplet of a liquid is placed on a surface where its contact angle is measured. High contact angle indicates cohesive > adhesive force (i.e. high surface tension) and low wetting. And vice-versa.

Question 103

Explain the Capillary Rise method

Answer 103

A capillary (thin tube) is immersed in a liquid. The height at which the liquid rises in the tube is inversely proportional to the amount of surface tension. Liquids that rises in the capillary above their surrounding liquid indicates cohesive < adhesive forces (i.e. low surface tension) and are concave at the top. A liquid that enters the tube but remains lower than its surroundings indicates cohesive > adhesive (i.e. high surface tension) and have a curve shape at the top.

Question 104

Explain the Wilhelmy Plate method

Answer 104

A plate is immersed in a liquid of interest and pulled upwards. The amount of force required to pull the plate is proportional to the surface tension. This is because liquids with strong cohesive forces will have molecules that are more strongly bound to each other. As a result, when the molecules in contact with the plate get pulled up, the other molecules also get pulled up, requiring more force to be applied to the plate.

Question 105

State 4 ways to quality test softgels

Answer 105

- Ribbon thickness and seal thickness stay constant - Fill matrix weight and capsule weight - Soft-gel moisture level and capsule hardness - Bloom strength