*The listing should be helpful to those just starting in HPLC but it also can serve as a refresher for long-time users in the field.*

## K

** k: **See

*retention factor.*** k:' **An old term that has been replaced by the IUPAC-approved term, retention factor (

*k*).

** K: **See

*partition coefficient.**k* _{A/B }** : **See

*selectivity coefficient.**K* _{c }** : **See

*distribution constant (coefficient).*** Kieselguhr: **A diatomaceous earth used in column chromatography and also as a sample cleanup media. Only weakly adsorptive, it can be used as a support in liquid–liquid chromatography. Rarely used in HPLC.

** Kinetic plot: **Kinetic plots are methods to characterize the practical limits of column performance, where theoretical plates (

*H*) and separation impedance (

*E*) are plotted as a function of the pressure-drop limited plate number (

*N*). The kinetic plot retains the information shown in van Deemter plots but completes it with the information on the bed permeability. See

**.**

*Poppe plot*** Knox equation: **A modification of the van Deemter equation developed by John Knox in which the A term that represents eddy dispersion multiplied by

*u*¼, where

*u*is the interstitial eluent velocity. Usually written in terms of the dimensionless or reduced plate height (

*h*) and reduced velocity (ν) as

*h*= Aν¼ + B/ν + Cν. See also

*van Deemter equation.*👩🔬"We hope you liked this article about **Glossary Of HPLC-LC Separation Terms – K**"👩🔬