Question #fc328
3 Answers
It's a group of laboratory methods used for the separation of mixtures.
The mixture (whether liquid or solid) is first dissolved into a liquid that goes through the chromatography apparatus. This liquid is called the Mobile Phase.
The mobile phase will go inside the apparatus and through a solid material. This solid material is called the Stationary Phase.
The stationary phase is usually a porous resin that is either neutral or electrically charged.
The purpose of the stationary phase is to "hinder" the passage of the mixture's components in a way where they will exit as separate compounds.
Bigger molecules or molecules with higher electrical charge will move slower through the stationary phase in relation to smaller or less charged molecules.
This will allow the smaller or less charged molecules to exit the stationary phase and hence, the apparatus first, then followed by the bigger or more charged molecules.
This is the general idea of chromatography, there are many variations and more detailed procedures for different types of mixtures. Check them below.
Sources & further reading:
Chromatography
A video on chromatography paper.
Chromatography basically means separation.
Explanation:
A stationary phase is coated either onto a column or a flat surface, can either be a solid or a liquid that is of a polar or non-polar nature.
The mobile phase which is a liquid or gas, contains your mixture, that contains your analyte, is passed through the column or flat surface is dipped into mobile phase and a series of interaction occurs.
There is an equilibrium between mobile and stationary phase such that the mixture is separated into its individual components as time goes by.
Like attracts like, so if stationary phase is polar the most polar component in your mixture is retained the longest and comes out last. And non-polar stationary phase retains non-polar component longest.
In Gas Chromatography and Liquid Chromatography, detectors detect the different components as a signal and gives a Chromatogram which shows different peaks which is related to your components and from that, the amount (concentration) can be calculated via integration and comparison with standards of known concentration.
A Chromatogram showing the different peaks of different components that were separated:
Image from: http://ishigirl.tripod.com/pchem/gc_ms.html
Hope this helps :)
A video on chromatography paper.
Chromatography is a process of separation
Explanation:
Chromatography is a process of separation in which 2 or more solids dissolves in a liquid are separated from each other. This is due to difference in their solubility.
Ex.- separation of ink into its dye components
