Questions and answers for exam Preparation

MCQs

Total Questions : 147 | Page 7 of 15 pages

Question 61. An isocratic elution in HPLC is one in which the composition of the solvent

remains constant
changes continuously
changes in a series of steps
none of these

Discuss Question

Answer: Option A. -> remains constant
Answer: (a).remains constant

Question 62. An eluotropic series

ranks solvents by their relative abilities to displace solutes from a given absorbent
ranks column packing material by their relative abilities to retain solutes on the column
is a measure of the solvent adsorption energy
none of the above

Discuss Question

Answer: Option A. -> ranks solvents by their relative abilities to displace solutes from a given absorbent
Answer: (a).ranks solvents by their relative abilities to displace solutes from a given absorbent

Question 63. In reversed phase HPLC, there is a

non polar solvent/polar column
polar solvent/non-polar column
non polar solvent/non-polar column
any of the above

Discuss Question

Answer: Option B. -> polar solvent/non-polar column
Answer: (b).polar solvent/non-polar column

Question 64. Which of the following statements is true for a refractive index detector in HPLC?

It is more sensitive than a UV detector
It can only be used for isocratic elutions
It does not respond to many solutes
none of above

Discuss Question

Answer: Option C. -> It does not respond to many solutes
Answer: (c).It does not respond to many solutes

Question 65. A gradient elution in HPLC is one in which the composition of the solvent

remains constant
is changed continuously or in a series of steps
both (a) and (b)
none of the above

Discuss Question

Answer: Option B. -> is changed continuously or in a series of steps
Answer: (b).is changed continuously or in a series of steps

Question 66. Dwell volume is defined as

the volume of solvent contained in a liquid chromatographic column
the time required for the gradient to reach the column
the volume of the column between the point at which solvents are mixed and the beginning of the column
none of these

Discuss Question

Answer: Option C. -> the volume of the column between the point at which solvents are mixed and the beginning of the column
Answer: (c).the volume of the column between the point at which solvents are mixed and the beginning of the column

Question 67. In normal phase HPLC, there is a

non polar solvent/polar column
polar solvent/non-polar column
non polar solvent/non-polar column
any of the above

Discuss Question

Answer: Option A. -> non polar solvent/polar column
Answer: (a).non polar solvent/polar column

Question 68. Which can be used as a mobile phase in HPLC applications?

Any compound with solubility in liquid
Any compound with limited solubility in liquid
Any compound with non-solubility in liquid
Any of the above

Discuss Question

Answer: Option A. -> Any compound with solubility in liquid
Answer: (a).Any compound with solubility in liquid

Question 69. Which of the following(s) is/are the advantage of HPLC over traditional LPLC (low-pressure liquid chromatography)?

Greater sensitivity and reusable columns
Ideal for ionic species and large molecules
Sample recovery
All of the above

Discuss Question

Answer: Option D. -> All of the above
Answer: (d).All of the above

Question 70. Void volume refers to the

total volume of eluent in the column the remainder being taken up by the packing material
the volume of solvent contained in a liquid chromatographic column
the time required for the gradient to reach the column
the volume of the column between the point at which solvents are mixed and the beginning of the column

Discuss Question

Answer: Option A. -> total volume of eluent in the column the remainder being taken up by the packing material
Answer: (a).total volume of eluent in the column the remainder being taken up by the packing material