Introduction to Chromatography Flashcards by Khristine Tapado

Chromatography is a physical method that is used to
separate and analyse __________
a) Simple mixtures
b) Complex mixtures
c) Viscous mixtures
d) Metals

b) Complex mixtures

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In which type of chromatography, the stationary phase
held in a narrow tube and the mobile phase is forced
through it under pressure?
a) Column chromatography
b) Planar chromatography
c) Liquid chromatography
d) Gas chromatography

a) Column chromatography

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In chromatography, the stationary phase can be
___________ supported on a solid.
a) Solid or liquid
b) Liquid or gas
c) Solid only
d) Liquid only

a) Solid or liquid

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In chromatography, which of the following can the
mobile phase be made of?
a) Solid or liquid
b) Liquid or gas
c) Gas only
d) Liquid only

b) Liquid or gas

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Which of the following cannot be used as an adsorbent
in Column adsorption chromatography?
a) Magnesium oxide
b) Silica gel
c) Activated alumina
d) Potassium permanganate

d) Potassium permanganate

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Which of the following types of chromatography
involves the separation of substances in a mixture over a
0.2mm thick layer of an adsorbent?
a) Gas liquid
b) Column
c) Thin layer
d) Paper

c) Thin layer

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Chromatography cannot be used to purify volatile
substances.
a) True
b) False

b) False

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In Column chromatography, the stationary phase is
made of _________ and the mobile phase is made of
_________
a) Solid, liquid
b) Liquid, liquid
c) Liquid, gas
d) Solid, gas

a) Solid, liquid

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Chromatography cannot be used to separate delicate
products.
a) True
b) False

b) False

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In Thin layer chromatography, the stationary phase is
made of _________ and the mobile phase is made of
_________
a) Solid, liquid
b) Liquid, liquid
c) Liquid, gas
d) Solid, gas

a) Solid, liquid

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In Gas-liquid phase chromatography, the stationary
phase is composed of _________ and the mobile phase is
made of _________
a) Solid, liquid
b) Liquid, liquid
c) Liquid, gas
d) Solid, gas

c) Liquid, gas

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In which of the following type of paper,
chromatography does the mobile phase move horizontally
over a circular sheet of paper?
a) Ascending paper chromatography
b) Descending paper chromatography
c) Radial paper chromatography
d) Ascending – descending chromatography

c) Radial paper chromatography

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Liquid chromatography can be performed in which of
the following ways?
a) Only in columns
b) Only on plane surfaces
c) Either in columns or on plane surfaces
d) Neither in columns nor on plane surfaces

c) Either in columns or on plane surfaces

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Gas chromatography can be performed in which of the
following ways?
a) Only in columns
b) Only on plane surfaces
c) Either in columns or on plane surfaces
d) Neither in columns nor on plane surfaces

a) Only in columns

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Which of the following types of chromatography
involves the process, where the mobile phase moves
through the stationary phase by the influence of gravity or
capillary action?
a) Column Chromatography
b) High Pressure Liquid Chromatography
c) Gas Chromatography
d) Planar Chromatography

d) Planar Chromatography

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Which of the following steps takes place after injection
of feed in Column chromatography?
a) Detection of components
b) Separation in the column
c) Elution from the column
d) Collection of eluted component

a) Detection of components

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What happens during the ‘elution from the column’
phase in chromatography?
a) Components with greatest affinity elute first
b) Components with least affinity elute first
c) Components elute in a random manner
d) Components elute according to their concentration in
the mixture

b) Components with least affinity elute first

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Components with a strong attraction to the support
move more slowly than components with weak attraction.
a) True
b) False

a) True

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In chromatogram, the position of peaks on the time axis
can be used to determine which of the following?
a) Components of the sample
b) Amount of component in the sample
c) Column efficiency
d) Column resolution

a) Components of the sample

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In chromatogram, the area under the peak can be used
to determine which of the following?
a) Components of the sample
b) Amount of component in the sample
c) Column efficiency
d) Column resolution

b) Amount of component in the sample

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The stationary phase could be a viscous liquid coated
over a surface of solid particles.
a) True
b) False

a) True

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Using Chromatogram as detector in Chromatography, a
graph is obtained between ____________ and time.
a) Quantity
b) Density
c) Concentration
d) Specific gravity

c) Concentration

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How is the molar concentration of solute in stationary
phase related to molar concentration of solute in the
mobile phase?
a) Directly proportional
b) Inversely proportional
c) Equal
d) Not related

a) Directly proportional

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In older analytical methods, which of the following
methods were used to allow movement of the mobile
phase?
a) Pumps
b) Pressure
c) Gravity
d) Blowing air into the column

c) Gravity

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2. If the value of the distribution constant ‘k’ is one, then what could be inferred about the distribution of solute? a) Its distribution in stationary phase is greater b) Its distribution in mobile phase is greater c) It is equally distributed in stationary and mobile phase d) It is distributed in a random manner

3. The time taken by the analyte after sample injection to reach the detector is called _________ a) Dead time b) Solute migration rate c) Adjusted retention time d) Retention time

d) Retention time

4. The time required for a molecule of the mobile phase to pass through the column is called ___________ a) Dead time b) Solute migration rate c) Adjusted retention time d) Retention time

a) Dead time

5. Adjusted retention time is the remaining retention time after subtracting __________ from ___________ a) Solute migration rate and retention time b) Retention time and solute migration rate c) Dead time and retention time d) Retention time and dead time

c) Dead time and retention time

6. Which of the following is the volume of mobile phase required to make a solute band move from the point of injection through the column to the detector? a) Dead volume b) Retention volume c) Void volume d) Adjusted retention volume

b) Retention volume

7. Adjusted retention volume is the remaining retention volume after subtracting ___________ from _____________ a) Solute migration rate and retention volume b) Retention volume and solute migration rate c) Dead volume and retention volume d) Retention volume and dead volume

c) Dead volume and retention volume

8. Which of the following is defined as the ratio of moles of solute in stationary phase to the moles of solute in the mobile phase? a) Distribution constant b) Volumetric phase ratio c) Retention factor d) Total porosity

c) Retention factor

9. Which of the following is the ratio of the interstitial volume of packing to the volume of its total mass? a) Distribution constant b) Volumetric phase ratio c) Retention factor d) Total porosity

d) Total porosity

10. Which of the following is the ratio of the length of column packing to dead time? a) Average linear rate of solute migration b) Average linear rate of mobile migration c) Relative migration rate d) Selectivity factor

b) Average linear rate of mobile migration

11. Which of the following is the ratio of a length of column packing to retention time? a) Average linear rate of solute migration b) Average linear rate of mobile migration c) Relative migration rate d) Selectivity factor

a) Average linear rate of solute migration

12. Retention distance is the distance between point of injection and minimum peak in the recorder or computer generated chart. a) True b) False

b) False

14. Retention factor is also known as the capacitance factor. a) True b) False

a) True

13. Retention volume can be obtained by finding the product of which of the following parameters? a) Dead time and total porosity b) Retention time and volumetric flow rate c) Adjusted retention time and volumetric flow rate d) Retention time and total porosity.

b) Retention time and volumetric flow rate

15. What must be the value of the selectivity factor? a) Equal to 1 b) Less than 1 c) Greater than 1 d) Greater than 0

c) Greater than 1

1. Which of the following is the distance that the solute moves while undergoing one partition? a) Retention distance b) Distribution constant c) Plate height d) Column packing length

c) Plate height

2. Which of the following conditions will cause the efficiency of the column to increase? a) Plate number becomes greater, plate height becomes smaller b) Plate number becomes smaller, plate height becomes smaller c) Plate number becomes greater, plate height becomes larger d) Plate number becomes greater, plate height becomes larger

a) Plate number becomes greater, plate height becomes smaller

3. Which of the following is the expression for Eddy diffusion in the column, if ‘γ’ represents obstruction factor, ‘dp’ represents particle diameter, ‘DM’ represents Solute diffusion co-efficient and ‘λ’ represents function for packing uniformity? a) λ dM b) 2 γ DM c) DM γ d) λ/dM

a) λ dM

4. Which of the following is the expression for longitudinal diffusion in the column, if ‘γ’ represents obstruction factor, ‘dM’ represents particle diameter, ‘DM’ represents Solute diffusion co-efficient and ‘λ’ represents function for packing uniformity? a) λ dM b) 2 γ DM c) DM γ d) λ/dM

b) 2 γ DM

5. In gas-liquid chromatography, when films are used in the interior of the capillary column, then what is the value of Eddy diffusion? a) Greater than 1 b) Less than 1 c) Zero d) Less than zero

c) Zero

6. For an unpacked coated capillary column, the obstruction factor takes which of the following values? a) 0 b) 0.6 c) 1 d) 1.6

c) 1

7. Base line resolution is achieved when degree of resolution/separation is ______ a) 1 b) 0 c) 0.5 d) 1.5

d) 1.5

8. Which of the following equations give the expression for plate number, N when ‘tR’ is the adjusted retention time and ‘Wb’ is the width at the base of the peak which is equal to 4 standard deviations. a) 16 tR 2/Wb b) 4 tR 2/Wb c) (4tR/Wb)^2 d) 4 (tR/Wb)2

c) (4tR/Wb)^2

1. For the separation of which of the following substances, Gas-solid chromatography is being used? a) Thermally stable organic components b) Volatile organic components c) Thermally stable inorganic components d) Low molecular weight gaseous species

d) Low molecular weight gaseous species

9. It is more difficult to measure the width at half peak height than the base width in the detector output. a) True b) False

b) False

10. The solute, while moving in the column is always in equilibrium with both the stationary phase and the mobile phase. a) True b) False

a) True

2. Which of the following is not a feature of carrier gas used in gas chromatography? a) It must be chemically inert b) It should be suitable for the detector employed c) It should not be completely pure d) It should be cheap

c) It should not be completely pure

3. Which of the following is the disadvantage of hydrogen, which can be used as carrier gas in gas chromatography? a) Dangerous to use b) Expensive c) Reduced sensitivity d) High density

a) Dangerous to use

4. Which of the following is the disadvantage of helium, which can be used as carrier gas in gas chromatography? a) Dangerous to use b) Expensive c) Reduced sensitivity d) High density

b) Expensive

5. Which of the following is the disadvantage of nitrogen, which can be used as carrier gas in gas chromatography? a) Dangerous to use b) Expensive c) Reduced sensitivity d) High density

c) Reduced sensitivity

6. Slow injection of large samples leads to band broadening and loss of resolution. a) True b) False

a) True

7. In which of the following methods are liquid samples injected into the column in gas chromatography? a) Gas tight syringe b) Micro-syringe c) Rotary sample valve d) Solid injection syringes

b) Micro-syringe

9. Which of the following is the commonly used support material for the packed column in gas chromatography? a) Glass b) Metal c) Diatomaceous earth d) Stainless steel

c) Diatomaceous earth

8. What must be done to the solid samples for it to be introduced into the column without using solid injection syringes in gas chromatography? a) Introduced in hot-zone of the column b) Dissolved in volatile liquids c) Introduced using rotary sample valve d) Introduced using sampling loop

b) Dissolved in volatile liquids

13. Sample injection port must be maintained at a temperature at which rapid vapourisation occurs but thermal degradation does not occur. a) True b) False

a) True

11. Which of the following is the disadvantage of coiled or helical shaped packed chromatographic column? a) It cannot be packed uniformly b) It cannot be repacked easily c) It is not compact d) It is not easy to heat it evenly

b) It cannot be repacked easily

12. Capillary columns are open tubular columns constructed from which of the following materials? a) Glass b) Metal c) Stainless steel d) Fused silica

d) Fused silica

10. Which of the following is the advantage of a straight packed column? a) It can be packed uniformly b) It can be repacked easily c) It is compact d) It is easier to heat it evenly

c) It is compact

14. Which of the following is not a desirable feature of the ovens used in gas chromatography? a) It must have a fast rate of heating b) Power consumption should be kept low c) It must have maximum thermal gradients d) It should have proper insulation

c) It must have maximum thermal gradients

1. Which of the following is not an ideal characteristic of a detector used in gas chromatography? a) Linear response to the solutes b) Short response time c) High reliability d) Sensitive to the changes in the flow rate of a carrier gas

d) Sensitive to the changes in the flow rate of a carrier gas

3. Which of the following detectors have high sensitivity to all organic compounds? a) Sulphur chemiluminescense detector b) Thermionic emission detector c) Flame ionization detector d) Argon ionisation detector

c) Flame ionization detector

2. Which of the following is not a type of detector used in gas chromatography? a) Argon ionisation detector b) Thermal conductivity detector c) UV visible spectrometric detector d) Electron capture detector

c) UV visible spectrometric detector

4. Which of the following is not the advantage of thermal conductivity detector used in gas chromatography? a) Simple in construction b) High sensitivity c) Large linear dynamic range d) Non-destructive character

b) High sensitivity

5. Which of the following detectors is widely used to detect environmental samples like chlorinated pesticides and polychlorinated biphenyls? a) Flame ionization detector b) Thermal conductivity detector c) Argon ionisation detector d) Electron capture detector

d) Electron capture detector

6. In which of the following detector is the eluent mixed with hydrogen and burned and then mixed with ozone and its intensity is measured? a) Sulphur chemiluminescense detector b) Thermal conductivity detector c) Flame ionization detector d) Electron capture detector

a) Sulphur chemiluminescense detector

8. Which of the following detector uses ultraviolet radiation from lamps to produce ionisation of solute molecules? a) Sulphur chemiluminescense detector b) Thermal conductivity detector c) Photo ionization detector d) Electron capture detector

c) Photo ionization detector

9. Flame ionisation detector is also known as Katharometer. a) True b) False

b) False

7. Filter photometer detector is primarily responsive to which of the following compounds/elements? a) Volatile sulphur or phosphorous compounds b) Nitrogen c) Halogen d) Potassium

a) Volatile sulphur or phosphorous compounds

10. Thermionic emission detector used in gas chromatography is most sensitive to which of the following elements? a) Nitrogen b) Phosphorous c) Halogen d) Carbon

b) Phosphorous

11. Which of the following detectors has a non-volatile bead of rubidium silicate placed above the flame tip? a) Argon ionisation detector b) Thermionic emission detector c) Flame ionization detector d) Electron capture detector

b) Thermionic emission detector

12. In which of the following detectors, the carrier gas is excited by a radioactive source and the atoms of carrier gas are excited to a metastable state? a) Argon ionisation detector b) Thermionic emission detector c) Flame ionization detector d) Electron capture detector

a) Argon ionisation detector

13. Which of the following is not used as a heating element in a Thermal conductivity detector? a) Platinum b) Gold c) Graphite d) Tungsten wire

c) Graphite

1. Gas-solid chromatography is based on which of the following processes? a) Partition of the analyte between a gaseous mobile phase and a stationary liquid phase b) Adsorption of gaseous substances on solid surface c) Ion exchange d) Large molecules cannot penetrate through the gel

b) Adsorption of gaseous substances on solid surface

14. Electron capture detector is much less susceptible to contamination when nickel is used instead of tritium. a) True b) False

a) True

2. Which of the following components cannot be retained by gas-liquid columns but can be separated by using gas solid chromatography? a) Formaldehyde b) Hydrogen sulphide c) Benzene d) Carbon dioxide

b) Hydrogen sulphide

3. Which of the following is not an advantage of gas-solid chromatography? a) Increased column life b) Can be used for separation of rare gases c) Leads to semi-permanent retention of the analyte d) Ability to retain some components that cannot be easily retained by other gas chromatography method

c) Leads to semi-permanent retention of the analyte

4. The distribution coefficients of Gas-solid chromatography are greater than that of Gas-liquid chromatography. c b) False

a) True

5. Which of the following columns can be used in Gas-solid chromatography? a) Open tubular column b) Analytical column c) Separation column d) Guard column

a) Open tubular column

6. Which of the following is not an advantage for the conversion of packed columns into wide bore capillaries? a) Longer retention times b) Longer life c) Higher efficiency d) Greater inertness

a) Longer retention times

7. Which of the following is not a disadvantage of gas-solid chromatography? a) Strong retention of polar solutes b) Lifetime is short c) Occurrence of catalytic changes d) Cannot be used for very wide range of components

b) Lifetime is short

8. Gas-solid chromatography can be used only for separation of certain low molecular weight gaseous species. a) True b) False

a) True

9. Which of the following is a special adsorbent used in gas-solid chromatography? a) Molecular sieves b) Silica gel c) Alumina d) Starch

a) Molecular sieves

10. Which of the following properties of molecular sieves make it ideal for exclusion mechanism of separation? a) High thermal stability b) Large inner surface area c) Variable framework charge d) Ability to distinguish materials on the basis of their size

d) Ability to distinguish materials on the basis of their size

1. Which of the following is the disadvantage of reciprocating pump used in liquid chromatography? a) Produces pulsed flow b) Corrosive components c) Does not have small hold-up value d) Does not have moderate flow rate

a) Produces pulsed flow

2. Which of the following is not a disadvantage of Pneumatic pumps used in liquid chromatography? a) Pulsed output b) Dependent on solvent viscosity c) Dependent on back pressure d) Inconvenient for solvent gradient elution

a) Pulsed output

4. Which of the following will improve the efficiency of the separation process in liquid chromatography? a) Increase in sample size, increase in column diameter b) Reduction in sample size, increase in column diameter c) Increase in sample size, reduction in column diameter d) Reduction in sample size, reduction in column diameter

d) Reduction in sample size, reduction in column diameter

3. Which of the following is not a desired characteristic of pulse dampers or flow smootheners used in liquid chromatography? a) Easy mobile phase change over b) Constant flow must be maintained c) Should be effective at low system pressure d) Maximal dead volume

d) Maximal dead volume

5. Which of the following are the practical problems that arise due to the decrease in column diameter? a) Requirement of large particle size and high pressure drop b) Requirement of large particle size and low pressure drop c) Requirement of small particle size and high pressure drop d) Requirement of small particle size and low pressure drop

c) Requirement of small particle size and high pressure drop

6. Which of the following is not true about the guard column used in liquid chromatography? a) It filters particles that clog the separation column b) It extends the lifetime of separation column c) It allows particles that cause precipitation upon contact with stationary or mobile phase d) The size of packing varies with the type of protection needed

c) It allows particles that cause precipitation upon contact with stationary or mobile phase

7. Which of the following columns are not used in liquid or high performance liquid chromatography? a) Analytical column b) Separation column c) Guard column d) Capillary column

d) Capillary column

8. Which of the following is not a Column-type Liquid chromatography? a) Gel permeation b) Ion exchange c) Liquid-solid d) Paper

d) Paper

9. Which of the following is not true about the radial compression column when compared to standard separation column? a) Internal diameter decreases b) Overall operating pressure decreases c) Analysis time decreases d) Solvent flow increases

a) Internal diameter decreases

10. Which of the following is not true about narrow bore column when compared to standard columns? a) Internal diameter decreases b) Volumetric flow decreases c) Solvent cost is saved d) Detector response time increases

d) Detector response time increases

11. Which of the following types of liquid chromatography uses immobilized biochemical as a stationary phase? a) Ion exchange chromatography b) Exclusion chromatography c) Affinity chromatography d) Gel permeation chromatography

c) Affinity chromatography

1. Which of the following is not true about High pressure liquid chromatography (HPLC)? a) It requires high pressure for the separation of the specious b) There is no need to vaporise the samples c) It is performed in columns d) It has high sensitivity

b) There is no need to vaporise the samples

2. High pressure liquid chromatography can be performed only in columns. a) True b) False

a) True

3. Which of the following is not an advantage of Syringe type pumps used in High pressure liquid chromatography? a) Independent of viscosity b) Pulse-less flow c) High pressure capability d) Unlimited solvent capacity

d) Unlimited solvent capacity

5. Which of the following pulse damper takes up some amount of the pulsation energy which is released to provide smooth pressure without pulsations? a) Flexible bellows or compressible gas passed through tee columns b) Flexible inert diaphragm c) Electronic pulse damper d) Electrical pulse damper

a) Flexible bellows or compressible gas passed through tee columns

4. Which of the following is not true about solvent programming which is done in high performance liquid chromatography? a) It provides unequal bandwidths b) It provides fast overall separation c) It provides maximum resolution d) It provides maximum sensitivity

a) It provides unequal bandwidths

7. Syringe pumps used in High pressure liquid chromatography are most suitable for which of the following columns? a) Capillary columns b) Guard columns c) Short-fast columns d) Small bore columns

d) Small bore columns

6. Which of the following is not a characteristic of the syringe pump used in high pressure liquid chromatography? a) Pressure capability is high b) Maintenance is frequent c) Limited reservoir capability d) Slight change of flow rate when extremely high pressure compresses the solvent

b) Maintenance is frequent

8. Gravity feed method for solvent delivery is not used with narrow bore columns packed with fine mesh particles. a) True b) False

a) True

9. Which of the following cannot be done to reduce ripple in High pressure liquid chromatography? a) Using bellows b) Using restrictors c) Using long nylon tube between pump and column d) Avoiding the use of the solvent pump

d) Avoiding the use of the solvent pump

10. Which of the following is not true about Hydraulic capacitance flow control system used in HPLC? a) It can be used only for liquids with low viscosity b) It is irrespective of solvent compressibility c) It maintains a constant flow d) It smoothens high pressure pump pulsations

a) It can be used only for liquids with low viscosity

1. Bulk property detectors used in liquid chromatography does not respond to which of the following properties? a) Refractive index b) Density c) Properties of solutes d) Dielectric constant

c) Properties of solutes

2. Which of the following is not a property of a good detector used in liquid chromatography? a) Good sensitivity b) Ability to function in the presence of a large background signal c) Short response time d) Volume of detector must be large

d) Volume of detector must be large

3. Detector selectivity is more important in Liquid chromatography than in Gas chromatography. a) True b) False

a) True

4. Which of the following UV absorbance detectors provide a real time spectrum of the component of interest? a) Continuous wavelength detector b) Variable wavelength detector c) Scanning wavelength detector d) Fixed wavelength detector

c) Scanning wavelength detector

5. Fluorescence detection is less selective than absorption detection. a) True b) False

b) False

6. Which of the following detectors depend on Snell’s law at the interface between the cell wall and the flowing liquid to deflect the light beam? a) Electrochemical detectors b) Fluorescence detectors c) Refractive index detectors d) Thermal conductivity detectors

c) Refractive index detectors

7. Refractive index detectors used in liquid chromatography are not based on which of the following processes? a) Interference b) Refraction c) Reflection d) Absorption

d) Absorption

9. The reference cell is packed with which of the following in the Adsorption detector used in liquid chromatography? a) Inactive glass beads b) Porous glass beads c) Alumina d) Silica

a) Inactive glass beads

8. Which of the following detectors can be used for detection of amino acids in protein hydrolyzates by introducing the reagent dansylchloride in the sample? a) Electrochemical detectors b) Fluorescence detectors c) Refractive index detectors d) Thermal conductivity detectors

b) Fluorescence detectors

10. Which of the following is true about Laser detectors used in liquid chromatography? a) Causes thermal distortion has decreased sensitivity b) Causes thermal distortion has increased sensitivity c) Does not cause thermal distortion, has decreased sensitivity d) Does not cause thermal distortion, has increased sensitivity

a) Causes thermal distortion has decreased sensitivity

11. Which of the following detectors used in liquid chromatography is also called micro-adsorption detector? a) Electrochemical detectors b) Fluorescence detectors c) Refractive index detectors d) Thermal detectors

d) Thermal detectors

12. In UV-Visible detectors, the cells are not made of which of the following materials? a) Quartz b) Teflon c) Silica d) KELF

c) Silica

13. Which of the following is not a feature of refractive index type detectors? a) Higher potential sensitivity b) Low cost c) High volume flow rates d) Easy cell accessibility

c) High volume flow rates

14. Which of the following detectors can detect almost any component? a) Combining two UV detectors b) Combining RI and UV detectors c) Mass detector d) Laser-based detectors

b) Combining RI and UV detectors