Chromatography

• separate and identify components in a mixture

• allows molecules to distribute themselves in mobile or stationary

Chromatography

• Fixed medium

• Part of the apparatus

• Where component interact

Stationary Medium/Stationary Phase

• Fluid that carries mixture to be separated

• Can be liquid or gas

Mobile Medium/Medium Phase

Differential

Shows a difference; distinctive

Natural attraction or force between things

Affinity

After the components are separated, it is then?

1. Analyze

2. Identify

3. Purify

4. Quantify

Examines mixture and their relationship to one another

Analyze

Determines identity of the mixture

Identify

Separates components for further study

Purify

Determines the amount of mixture and components in a sample

Quantify

• Molecules have different factors, so they travel at different speeds

• Can be measured using the distance the pigments travelled along the paper strip

Retardation Factor (RF)

For substances soluble in liquid, the Rf is close to?

1

For substances insoluble in liquid, the Rf is close to?

0

Types of Chromatography

1. Paper Chromatography

2. Thin Layer Chromatography

3. Gas Layer Chromatography

4. Liquid Chromatography

Separates dried liquid samples with a liquid solvent and a paper strip

Paper Chromatography

2 Principles of Paper Chromatography

1. Capillary Action

2. Solubility

Movement of liquid within the spaces due to cohesion, adhesion, and surface tension because its attraction to itself is stronger than gravity

Capillary Action

• Solutes dissolve into solvents that have similar properties (like dissolves like)

• Allows different solutes to be separated depending on their solubility

Solubility

• Uses absorbent material on flat glass or plastic plates

• Samples are not colored so a UV lamp is needed

Thin Layer Chromatography

Helium is used to move a gaseous mixture through a column of absorbent material

Gas Layer Chromatography

A mixture is passed through a column packed with solid particles that may or may not be coated with another liquid

Liquid Chromatography

Types of Liquid Chromatography

1. Liquid/Solid Chromatography

2. Liquid/Liquid Chromatography

3. Ion Exchange Chromatography

4. Gel Permeation Chromatography

Other term for Liquid/Solid Chromatography

Adsorption Chromatography

Competition for active sites on an absorbent

Liquid/Solid Chromatography

The stationary solid surface is coated with a 2nd liquid which is immiscible in the solvent

Liquid/Liquid Chromatography

Competition for different ionic compounds for active sites in ion-exchange resin

Ion Exchange Chromatography

Mechanical sorting of molecules based on the size in the solution

Gel Permeation Chromatography

Used to separate, identify, and quantify compounds

High Performance Liquid Chromatography/High Pressure Liquid Chromatography (HPLC)

Uses polar stationary phase and non-polar mobile phase

Normal Phase Chromatography

Non-polar stationary phase and aqueous moderately polar mobile phase

Reverse Phase Chromatography