Rf value is the degree of retention of a component retardation factor rf value does not have units since the both lower and upper cases are in distance. In chromatography, the retardation factor (r) is the fraction of an analyte in the mobile phase of a chromatographic system in planar chromatography in particular, the retardation factor r f is defined as the ratio of the distance traveled by the center of a spot to the distance traveled by the solvent front. Suppose you have two compounds, one polar and one non polar, in an diethyl ether solvent run it on a tlc and you see a high rf value for the polar and a low rf value for non polar, as expected. Chem 344 thin layer chromatography thin layer chromatography (tlc) is a useful technique for the separation and identification of compounds in mixtures. Your toughest technical questions will likely get answered within 48 hours on researchgate, the professional network for scientists.
1 gcse bitesize examinations general certificate of secondary education aqa science a chy1b unit chemistry c1b (oils, earth and atmosphere. Thin layer chromatography i abstract the purpose of this lab was to determine the rate of flow values (rf=distance of component/distance of solvent) for certain pigments. Insulation level are specified by r-value r-value is a measure of insulation’s ability to resist heat traveling through it the higher the r-value the better the thermal performance of. Rf calculator: wavelength, dbm, dbuv, w, dbuv/m, mw/cm^2, pj/cm^2, v & vswr this rf calculator has been developed by compliance engineering as a resource for individuals involved in emc and rf compliance measurements.
Diffcult cases - choosing the best elutant mixture there is always more than one combination of solvents could be used to achieve the desired rf value. The author shares a quick and simple method to aid in student reading of rf values in tlc. Thin-layer and column chromatography: identifying an unknown analgesic, determining an ideal mobile phase and monitoring the progress of the mitsunobu.
Rf value indicates the relationship of the distance moved by a pigment to the distance moved by a solvent the rf can be calculated by the following equation. A sheet requiring students to calculate the rf values for a series of chromatograms. Calculating retardation factor (rf) is part of the science of chromatography using a collection of laboratory techniques for separating substance mixtures the process involve passing the mixture. 20 a diels-alder reaction the diels-alder reaction is an important synthetic tool because it produces new six-membered rings with a high degree of stereoselectivity.
Rf value = distance migrated by the pigment / distance migrated by the solvent front. Instructions on how to do chromatography using coffee filters, acetone and a spinach leaf plant pigments separate and can be analyzed for rf. 4) a developed tlc plate has a solvent front of 6cm and a solute front of 3 cm what is the rf value of the compound.