Chemistry 2


  1. Chromatography is a process of separating mixtures.
  2. In order to perform chromatography you will need the following items:
    1. Chromatographic column (this is some sort of solid support)
    2. Solvent (this is often a liquid or a gas in which some mixture is dissolved)
    3. Mixture
  3. A mixture by definition is made of more than one substance. Each substance will have its own set of properties. The substances in a mixture can be separated if they have differences in their properties. Chromatography uses two different properties for separation
    1. Adsorption - the property of how well a substance in the mixture sticks to the chromatographic column. The higher the adsorption the slower the substance will move along the column.
    2. Solubility - the property of how well a substance in the mixture dissolves into the solvent. The higher the solubility the faster the substance will move along the column.
  4. By exploiting differences in these two properties we can make the different substances move at different speeds along a chromatographic column by choosing the appropriate solvent and column material.
An insect analogy for chromatographic separation
An example of gas chromatography
Images from: Fred Senese at Frostberg State Univ.

Explore the Flash plugin below to solidify your understanding of how chromatography works:
You may want to use these questions to guide your exploration.


Below is a demo of column chromatography.

Developed in conjunction with the Concord Consortium and with the support
of the National Science Foundation