INTRODUCTION TO CHROMATOGRAPHY Flashcards
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
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
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
- 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
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
- 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
- Chromatography cannot be used to purify volatile substances.
a) True
b) False
b) False
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
Chromatography cannot be used to separate delicate products.
a) True
b) False
b) False
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
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
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
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
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
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
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
b) Separation in the column
Components with a strong attraction to the support move more slowly than components with weak attraction.
a) True
b) False
a) True
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
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
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
The stationary phase could be a viscous liquid coated over a surface of solid particles.
a) True
b) False
a) True
Given below is a diagram of separation of two components of a mixture in a chromatographic column. From the diagram, infer which component has lesser affinity to the stationary phase.
a) W
b) X
c) Y
d) Z
c) Y
Using Chromatogram as detector in Chromatography, a graph is obtained between ____________ and time.
a) Quantity
b) Density
c) Concentration
d) Specific gravity
c) Concentration
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
Given below is the diagram of ‘Process of chromatographic column’. Identify the unmarked component in the process.
a) Reservoir
b) Collection tank
c) Microprocessor
d) Detector
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
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
c) It is equally distributed in stationary and mobile phase
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
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
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
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
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
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
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
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
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
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
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
Retention factor is also known as the capacitance factor.
a) True
b) False
a) True
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
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
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
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
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
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
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
Base line resolution is achieved when degree of resolution/separation is ______
a) 1
b) 0
c) 0.5
d) 1.5
d) 1.5
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 tR2/Wb
b) 4 tR2/Wb
c) (4tR/Wb)2
d) 4 (tR/Wb)2
c) (4tR/Wb)2
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
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
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
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
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
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
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
Slow injection of large samples leads to band broadening and loss of resolution.
a) True
b) False
a) True
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
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 loops
b) Dissolved in volatile liquids
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
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