Chapter 22, Problem 22.13P

(a)

Interpretation Introduction

Interpretation:

Number of plates and plate height and particles can be placed side-by-side in one theoretical plate has to be calculated.

Concept Introduction:

Expression to compute number of theoretical plate is as follows:

  $N=\frac{5.55t_{\text{r}}{}^2}{w_{1/2}^2}$

Here,

$t_{\text{r}}$ denotes analyte’s  retention time.

$w_{1/2}$ denotes peak width at half-height.

$N$ denotes number of theoretical plate.

It has been found that greater the equilibration steps narrower will be band so this suggests $N$ should be high for more resolution or narrower separation.

Expression to compute number of particles to be placed side by side is as follows:

  $\text{Number of particles}=\frac{H}{\text{Particle Diameter}}$

Expression to compute plate height is as follows:

  $H=\frac{L}{N}$

Here,

$N$ denotes number of theoretical plate.

$L$ denotes length of chromatographic column.

$H$ denotes plate height.

(b)

Interpretation Introduction

Interpretation:

Particles that can be placed side-by-side in one theoretical plate with optimum plate height of $\text{4 μm}$ and whether column is run for maximum resolution or speed has to be determined.

Concept Introduction:

Refer to part (a).