🧪 Analytical instruments MCQ Quiz Hub

1. Retention volume can be obtained by finding the product of which of the following parameters?
Dead time and total porosity
Retention time and volumetric flow rate
Adjusted retention time and volumetric flow rate
Retention time and total porosity.

2. Retention factor is also known as the capacitance factor.
True
False
all of the above
None of the mentioned

3. What must be the value of the selectivity factor?
Equal to 1
Less than 1
Greater than 1
Greater than 0

4. Which of the following is the distance that the solute moves while undergoing one partition?
Retention distance
Distribution constant
Plate height
Column packing length

5. Which of the following conditions will cause the efficiency of the column to increase?
Plate number becomes greater, plate height becomes smaller
Plate number becomes smaller, plate height becomes smaller
Plate number becomes greater, plate height becomes larger
Plate number becomes greater, plate height becomes larger

6. 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?
λ dM
2 γ DM
DM γ
λ/dM

7. 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?
λ dM
2 γ DM
DM γ
λ/dM

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

9. For an unpacked coated capillary column, the obstruction factor takes which of the following values?
0
0.6
1
1.6

10. Base line resolution is achieved when degree of resolution/separation is ______
1
0
0.5
1.5

11. 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.
16 tR2/Wb
4 tR2/Wb
(4tR/Wb)2
4 (tR/Wb)2

12. It is more difficult to measure the width at half peak height than the base width in the detector output.
True
False
all of the above
None of the mentioned

13. The solute, while moving in the column is always in equilibrium with both the stationary phase and the mobile phase.
True
False
all of the above
None of the mentioned

14. Which of the following is the disadvantage of hydrogen, which can be used as carrier gas in gas chromatography?
Dangerous to use
Expensive
Reduced sensitivity
High density

15. Which of the following is the disadvantage of nitrogen, which can be used as carrier gas in gas chromatography?
Dangerous to use
Expensive
Reduced sensitivity
High density

16. Slow injection of large samples leads to band broadening and loss of resolution.
True
False
all of the above
None of the mentioned

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

18. Which of the following components cannot be retained by gas-liquid columns but can be separated by using gas-solid chromatography?
Formaldehyde
Hydrogen sulphide
Benzene
Carbon dioxide

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

20. The distribution coefficients of Gas-solid chromatography are greater than that of Gas-liquid chromatography.
True
False
all of the above
None of the mentioned

21. Which of the following columns can be used in Gas-solid chromatography?
Open tubular column
Analytical column
Separation column
Guard column

22. Which of the following is not an advantage for the conversion of packed columns into wide bore capillaries?
Longer retention times
Longer life
Higher efficiency
Greater inertness

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

24. Gas-solid chromatography can be used only for separation of certain low molecular weight gaseous species.
True
False
all of the above
All of the Mentioned

25. Which of the following is a special adsorbent used in gas-solid chromatography?
Molecular sieves
Silica gel
Alumina
Starch

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

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

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

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

30. Which of the following will improve the efficiency of the separation process in liquid chromatography?
Increase in sample size, increase in column diameter
Reduction in sample size, increase in column diameter
Increase in sample size, reduction in column diameter
Reduction in sample size, reduction in column diameter

31. Which of the following are the practical problems that arise due to the decrease in column diameter?
Requirement of large particle size and high pressure drop
Requirement of large particle size and low pressure drop
Requirement of small particle size and high pressure drop
Requirement of small particle size and low pressure drop

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

33. Which of the following columns are not used in liquid or high performance liquid chromatography?
Analytical column
Separation column
Guard column
Capillary column

34. Which of the following is not a Column-type Liquid chromatography?
Gel permeation
Ion exchange
Liquid-solid
Paper

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

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

37. Which of the following types of liquid chromatography uses immobilized biochemical as a stationary phase?
Ion exchange chromatography
Exclusion chromatography
Affinity chromatography
Gel permeation chromatography

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

39. High pressure liquid chromatography can be performed only in columns.
True
False
all of the above
None of the mentioned

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

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

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

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

44. Syringe pumps used in High pressure liquid chromatography are most suitable for which of the following columns?
Capillary columns
Guard columns
Short-fast columns
Small bore columns

45. Gravity feed method for solvent delivery is not used with narrow bore columns packed with fine mesh particles.
True
False
all of the above
None of the mentioned

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

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

48. Bulk property detectors used in liquid chromatography does not respond to which of the following properties?
Refractive index
Density
Properties of solutes
Dielectric constant

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

50. Detector selectivity is more important in Liquid chromatography than in Gas chromatography.
True
False
all of the above
None of the mentioned