Chapter 25, Problem 25.44P

a)

Interpretation Introduction

Interpretation:

The gradient time ${\text{t}}_{\text{G}}$ for $\text{15×0}\text{.46}\text{cm}$ column containing $\text{3μm}$ particles with flow rate of $\text{1}\text{.0}\text{ml/min}$ has to be calculated.

Concept Introduction:

Average retention factor:

For gradient/isocratic elution, the average retention factor ${\text{k}}^{\text{*}}$ for each solute is calculated from the equation,

${\text{k}}^{\text{*}}\text{=}\frac{{\text{t}}_{\text{G}}\text{F}}{{\text{ΔΦV}}_{\text{m}}\text{S}}$

Where ${\text{t}}_{\text{G}}$= gradient time (in min)

F=rate of flow (ml/min)

$\text{ΔΦ}$ = change in composition of solvent during the gradient

${\text{V}}_{\text{m}}$ = Volume of mobile phase in column (mL)

$\text{S}$ = slope in the linear-solvent strength model

b)

Interpretation Introduction

Interpretation:

${\text{k}}^{\text{*}}$ for optimized separation, gradient time and the flow rate of volume and the amount of sample load has to be calculated.

Concept Introduction:

Average retention factor:

For gradient/isocratic elution, the average retention factor ${\text{k}}^{\text{*}}$ for each solute is calculated from the equation,

${\text{k}}^{\text{*}}\text{=}\frac{{\text{t}}_{\text{G}}\text{F}}{{\text{ΔΦV}}_{\text{m}}\text{S}}$

Where ${\text{t}}_{\text{G}}$= gradient time (in min)

F=rate of flow (ml/min)

$\text{ΔΦ}$ = change in composition of solvent during the gradient

${\text{V}}_{\text{m}}$ = Volume of mobile phase in column (mL)

$\text{S}$ = slope in the linear-solvent strength model