TRAVISTRA

 GAS CHROMATOGRAPHY It is used for the separation as well as analysis of gaseous mixture and volatile organic compounds. Principle The components of a mixture are separated depending upon the extent of adsorption or partition of the stationary phase and at the rate at which the component is carried out by the mobile phase.  The mobile phase is a gas like Argon, Nitrogen, Helium, or hydrogen. The stationary phase may be solid or liquid. If the stationary phase consists of a solid material like silica, alumina, then chromatography is termed as Gas Solid Chromatography (GSC), and if the stationary phase is a liquid held as a thin layer on a solid support, then the technique is known as Gas-Liquid Chromatography (GLC)GSC- adsorption. GLC- partition INSTRUMENTATION  Carrier gas: It is allowed to flow through the system, carrying the sample in the vapor state through the column. It should be chemically inert, suitable for the detector employed, it should give the best column pe...

 THIN LAYER CHROMATOGRAPHY It is a chromatographic separation method used to separate mixtures, to check the purity of a mixture, and to monitor the progress of the reaction. Procedure A glass plate coated with a material of the adsorbent will constitute the stationary phase. The material is made into a slurry or a paste and the glass plate is coated with it by a thin layer applicator and dried. This glass plate with a thin layer of stationary phase is called chromatoplate. The mixture to be separated is applied to one end of the plate and it is placed in the solvent. When the solvent reaches near the top, it is removed and dried. If the components are colored the spots can be readily located. If the components are colorless the dried plate is sprayed with a suitable reagent to make the spot colored. In this way, the position of the components is located and their Rf values are determined. Rf value is the ratio of the distance traveled by a component to the distance traveled by the...