Abstract This paper looks at chromatography, an analytical technique based on the principle of selective adsorption that is used for the chemical separation of mixtures and substances. It examines how it is an important field of chemistry, which deals with the separation of pure substances from complex mixtures, and is widely used in the analysis of foods, drugs, blood, petroleum products, and radioactive-fission products. It also examines how variants of "column" chromatography have been developed since its discovery in 1906, including partition, liquid, paper, thin-layer, and gas-liquid chromatography.
From the Paper "Chromatography was discovered in 1906 by the Russian botanist Mikhail Tswett who first coined the term (derived from the Latin for "color writing"). The technique used by Tswett for separating the pigments (chlorophyll) of plants consisted of pouring petroleum-ether extract of green leaves over a column of powdered calcium carbonate in a vertical glass tube. As the solution seeped through the column the individual components of the mixture moved downward at different rates of speed, and the column became marked with horizontal bands of colors. Tswett did not enjoy a happy relationship with fellow scientists of his time, as they derided his results, and his technique, with Tswett responding in kind. As a result, it wasn?t until the 1930s that his methods were accepted as a breakthrough in chromatography."
Abstract The objective of this experiment was to determine the adsorption of various acetic acid solutions onto charcoal. This experiment obeyed the Langmuir isotherm because the plot of C/N versus C proved to be linear. This shows that the adsorption equilibrium is essentially ideal and there is a definite set of sites of adsorption.
From the Paper "The surface tension of deionized water and eight solution of n-butanol were determined using the capillary-rise method. The radius of the capillary was determined to be 3.59 x 10-2 + 0.15 cm. The value of the radius of the capillary allowed for the determination of the surface tensions of the eight n-butanol solutions. The surface tensions were then plotted versus the natural logarithm of the concentrations of the n-butanol solutions. The slope of the graph was then used to determine the amount of n-butanol adsorbed. This value was calculated to be 3.52 x 10-10 + 0.71 mol/cm2. This value was converted into 2.12 x 1014 + 0.71 molecules/cm2. The effective cross section area of one molecule of n-butanol was determined to be 4.72 x 10-15 + 0.71 cm2. The value of Avogrado's number was calculated using the value of n2/A and the molar volume of n-butanol. Avogrado's number was determined to be 2.74 x 1024 + 0.71."
