**KJEM230,
Chromatographic animations**

Diffusion

Brownian
motion

Diffusion

Basic
principle of Chromatography

Extraction

Repeated
extraction

Repeated
extraction with higher mixing frequency

Chromatography

Factors
for resolution, the Purnell equation

Sufficient
resolution

Reduced
efficiency, *N*

Reduced
selectivity, *α*

Reduced
retention, *k*

Zone
broadening, the Golay equation and optimal velocity

Very
low mobile phase velocity, *u*
= 50 mm/s

Low
mobile phase velocity, *u *=
100 mm/s

Moderate
mobile phase velocity, *u *=
200 mm/s

High
mobile phase velocity, *u*
= 400 mm/s

Very
high mobile phase velocity, *u
*= 800 mm/s

The
resulting optimal velocity