Column Efficiency and Column Resolution

Question 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

Answer 1

c) Plate height

Question 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

Answer 2

a) Plate number becomes greater, plate height becomes smaller

Question 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

Answer 3

a) λ dM

Question 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

Answer 4

b) 2 γ DM

Question 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

Answer 5

c) Zero

Question 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

Answer 6

c) 1

Question 7

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

Answer 7

d) 1.5

Question 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 tR2/Wb
b) 4 tR2/Wb
c) (4tR/Wb)2
d) 4 (tR/Wb)2

Answer 8

c) (4tR/Wb)2

Question 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

Answer 9

b) False

Question 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

Answer 10

a) True