100+ MCQs on Chromatography

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

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

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3. 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

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4. 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

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5. 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

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6. 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

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7. 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

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8. 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

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9. 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

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10. 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

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11. 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

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12. 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

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13. 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

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14. 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

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

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16. In a 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 components in the sample
c) Column efficiency
d) Column resolution

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

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18. Given below is a diagram of the separation of two components of a mixture in a chromatographic column. From the diagram, infer which component has a lesser affinity to the stationary phase.
a) W
b) X
c) Y
d) Z

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

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20. 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

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21. Given below is the diagram of the ‘Process of chromatographic column’. Identify the unmarked component in the process.
a) Reservoir
b) Collection tank
c) Microprocessor
d) Detector

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

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23. 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

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24. 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

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25. 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

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26. 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

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27. 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

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28. 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

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

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30. 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

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31. 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

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32. Which of the following is the ratio of the 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

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33. 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.

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34. 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

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35. 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

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36. 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

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37. 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 a function for packing uniformity?
a) λ dM
b) 2 γ DM
c) DM γ
d) λ/dM

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38. 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 a function for packing uniformity?
a) λ dM
b) 2 γ DM
c) DM γ
d) λ/dM

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39. 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

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40. 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

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

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42. 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

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43. 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

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44. 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

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

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

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

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48. 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

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49. 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

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50. 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

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51. 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

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52. 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

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

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54. 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

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55. Given below is the block diagram of gas chromatography. Identify the unmarked component.
a) Pumping system
b) Pressure regulator
c) Flow regulator
d) Sample injection system

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56. 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

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57. 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

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

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

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60. 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

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61. 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

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62. 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

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

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

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65. 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

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66. 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

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67. 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

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68. Given below is a diagram of an electron capture detector. Identify the unmarked component in the diagram.
a) Glass shield
b) Electrode
c) Quartz shield
d) Radioactive β- emitter

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69. 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

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70. 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

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71. Which of the following is not an advantage of gas-solid chromatography?
a) Increased column life
b) Can be used for the 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 methods

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72. 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

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73. 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

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74. 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

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

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76. Which of the following properties of molecular sieves make them ideal for the 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

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77. Which of the following is the disadvantage of the 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

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78. 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

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79. 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

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80. 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

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81. 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

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82. 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 the separation column
c) It allows particles that cause precipitation upon contact with the stationary or mobile phase
d) The size of packing varies with the type of protection needed

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83. 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

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

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85. 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

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86. 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

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87. 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

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88. 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

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89. 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

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90. 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

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91. 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

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92. 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

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93. 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

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94. 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

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95. 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

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96. 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

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97. 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

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98. 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

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99. Which of the following detectors depends 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

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

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101. 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

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102. 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

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103. 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

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104. 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

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

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106. 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

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107. 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

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108. Given below is the diagram of Ultraviolet detector used in liquid chromatography. Identify the unmarked component.
a) Collimator
b) Lens
c) Monochromator
d) Quartz window

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109. What is the drawback that occurs in using ion exchange chromatography on sulfonated polystyrene resin and colorimetry for amino-acid analysis?
a) Less accuracy
b) Low resolution
c) Inconvenient to handle many individual samples
d) Slow in operation

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110. Which one of the following methods is the most suitable for amino-acid analysis?
a) Gas chromatography
b) Ion exchange chromatography
c) Paper electrophoresis
d) Resin column chromatography

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111. Which of the following colour reagents are used in Resin column chromatography?
a) Marquis reagent
b) Benedict reagent
c) Ninhydrin
d) Nessler’s reagent

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112. Which of the following amino-acids is measured at a wavelength of 440nm using photometric systems?
a) Proline
b) Alanine
c) Glutamine
d) Valine

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113. In the Automatic amino-acid analyzer, the sample containing ___________ of each amino compound is introduced at the top of the ion exchange column.
a) 1 to 10 µmoles
b) 1 to 10 moles
c) 0.05 to 2 moles
d) 0.05 to 2 µmoles

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114. Which of the following cannot be analysed using resin column chromatography?
a) Peptides
b) Amines
c) Amino compounds
d) Components which are ninhydrin negative

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115. Trapped air in pumps of Automatic amino-acid analyzer is eliminated using which of the following ways?
a) Suction pump
b) De-aerator
c) Overcome naturally by pump pressure
d) Using pulse damper

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116. What is the drawback that occurs in using gas chromatography for amino-acid analysis?
a) Costly
b) Cannot be used for proteins or polypeptides
c) Slow process
d) Complex in operation

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