911. The general expression for the appearance of a solute in an effluent is (where V is the elution volume of a substance , V0 void volume, kD distribution constant and Vi internal water volume)
A. V = V0 + kDVi
B. V = V0/Vi
C. V = V0 – kDVi
D. V/V0 = kDVi
912. A combination of paper chromatography and electrophoresis involves
A. partition chromatography
B. electrical mobility of the ionic species
C. both (a) and (b)
D. none of these
913. HPLC stands for
A. High Pressure Liquid Chromatography
B. High Performance Liquid Chromatography
C. both (a) and (b)
D. Highly Placed Liquid Chromatography
914. The eluent strength is a measure of
A. solvent adsorption energy
B. solvent absorption energy
C. solvent diffusivity
D. solvent mixing index
915. HPLC methods include
A. liquid/liquid (partition) chromatography
B. liquid/solid (adsorption) chromatography
C. ion exchange and size exclusion chromatography
D. all of the above
916. Column efficiency is measured in terms of number of plates which is
A. inversely related to the square of the peak width
B. directly related to the square of the peak width
C. inversely related to the cube root of the peak width
D. directly related to the square of the peak width
917. For a typical adsorbent such as silica gel, the most popular pore diameters are
A. 10 and 50 A°
B. 60 and 100 A°
C. 100 and 150 A°
D. 150 and 200 A°
918. An isocratic elution in HPLC is one in which the composition of the solvent
A. remains constant
B. changes continuously
C. changes in a series of steps
D. none of these
919. In reversed phase HPLC, there is a
A. non polar solvent/polar column
B. polar solvent/non-polar column
C. non polar solvent/non-polar column
D. any of the above
920. Which of the following statements is true for a refractive index detector in HPLC?
A. It is more sensitive than a UV detector
B. It can only be used for isocratic elutions
C. It does not respond to many solutes
D. none of above