Chromatography is a laboratory technique used to separate and identify the components of a mixture. It relies on the principle that different compounds in a mixture will interact differently with a stationary phase and a mobile phase, causing them to move at different rates and thus become separated.
Types of Chromatography
There are several types of chromatography, including:
Thin Layer Chromatography (TLC): In TLC, a thin layer of adsorbent material is coated on a glass, metal, or plastic plate. The sample mixture is applied near the bottom of the plate and the plate is then placed in a solvent. As the solvent moves up the plate, it carries the sample mixture with it, and the components of the mixture separate based on their interactions with the adsorbent material.
Gas Chromatography (GC): In GC, the sample is vaporized and injected into a long, coiled tube containing a stationary phase. A carriergas (such as helium or nitrogen) carries the vaporized sample through the tube. The different components of the sample interact with the stationary phase at different rates, causing them to separate as they exit the tube.
Liquid Chromatography (LC): In LC, the sample is dissolved in a liquid solvent and passed through a column containing a stationary phase. The components of the sample interact with the stationary phase and the solvent at different rates, causing them to separate as they flow through the column.
Applications of Chromatography
Chromatography has a wide range of applications in various fields, including:
Physics: Students will use scientific skills and processes to explain the interactions of matter and energy and the energy transformations that occur.
Thermodynamics: Identify and explain that heat energy is a product of the conversion of one form of energy to another.
Identify and describe the various forms of energy that are transformed in order for systems (living and non-living) to operate: Chemical - Flashlight-Light; Mechanical - Pulleys-Motion; Solar/Radiant - Solar calculator; Chemical - Plant cells.