Chromatography vs. Spectroscopy
Difference Between Chromatography And Spectroscopy
Chromatography is among the most important tools in analytical chemistry. It involves physically separating the different chemical substances in a mixture based on the different speeds at which they travel through a stationary material, or medium. The sample being analyzed is prepared in either liquid or gas form. The medium is either a solid or a liquid held in place by a solid. Since the different molecules in the sample travel at different rates through the medium, they separate out in a series of bands.
Spectroscopic analysis typically involves heating a chemical compound in an electric arc or flame. The heated compound gives off specific wavelengths of light depending on the elements that it contains. The chemist can analyze this spectrum, or separation of colors, visually or electronically to match different patterns of light with specific elements.
The spectrophotometer is similar to the spectrograph, except that it identifies chemicals by passing beams of light through a material rather than by burning it. The chemist determines the makeup of a sample by measuring the amount of each light wavelength that the material absorbs. The different types of spectrophotometers analyze for specific wavelengths, such as infrared (IR) or ultraviolet (UV).
The mass spectrometer has become one of chemistry’s most powerful analytical devices. It employs a combination of magnetic and electrostatic fields to separate positive ions according to their masses. The sample being studied is ionized, usually by bombarding it with high-energy electron beams, before it is subjected to the fields that separate its components. Recent advances have revolutionized the field of mass spectrometry and permitted researchers to apply this technique to large biomolecules.