How do extractions differ from chromatography?

Big Bang HTL 2, textbook

Basics of Chemistry (2nd year, 3rd semester) 17 The substances 1 Summary If the components of a mixture differ in their solubility in a solvent, they can be separated by extraction. The choice of a suitable solvent is crucial. Water is suitable for hydrophilic substances: Use in the production of sugar and salt. B. Gasoline are suitable for hydrophobic substances. 1.4.6 The Race of (Dyes) Substances - Chromatography Separation on the basis of solubility III In contrast to distillation, chromatography is a fairly new method, originating around 1900. The name comes from the Greek “chroma” = color and “graphhein” = to write. Chromatography can loosely be described as the race of dyes. Basic principle: A mixture is applied to a carrier material (e.g. paper) and a solvent is passed over it. The individual components of the mixture dissolve differently in the solvent (also called eluent). That is why they migrate along the carrier material at different speeds. The better a component dissolves in the solvent, the faster it migrates. The worse a component dissolves in the solvent, the longer it stays on the carrier material and the slower it migrates. The solvent is also called the mobile phase and the carrier material is also called the stationary phase. Z Separation based on solubility II Explain the steps of making coffee from a scientific point of view: Name and describe all mixtures and separation methods that occur! L Explain the terms hydrophilic and hydrophobic using examples that you have chosen. Explain why choosing the right solvent is critical for an extraction. L 1.4.5 F33 B2 F34 A1 What is a qualitative analysis and what is a quantitative one? Doping in sport is always a problem. How can you track down doping sinners? F35 F36 There are different types of chromatography: Paper chromatography (PC) Paper chromatography is the simplest type of chromatography. Simple filter paper is used as the carrier material, and the solvent is usually water. This allows colors to be separated from fiber pens. This is probably the most classic of all student experiments on the subject of chromatography. Technically, this method is hardly used. PC can be carried out on round filters (V 1.7) or on rectangular filter papers. Thin-layer chromatography (TLC) Thin-layer chromatography is so named because the separation takes place on a thin layer (eg made of silica gel, cellulose or aluminum oxide). Depending on the separation requirement, very different substances can be used as the eluent, from water to alcohol to a wide variety of organic solvents. The mixture to be separated is applied to the layer in small dots and then the whole thing is placed in a chamber, filled with solvent to cover the floor. The solvent is now sucked up along the layer and takes the various components of the mixture with it to varying degrees, thereby separating them. V 1.7 Paper chromatography Equipment and chemicals: Round filter, beaker, water, felt-tip pens Procedure: Drill a small hole in the center of a round filter. Use a felt pen (dark colors work best!) To draw dots about 1mm in diameter around the hole. Form a small roll out of a second filter paper and insert it into the filter paper with the colored dots. Hang in a beaker with water so that water can be sucked up over the roller. Tasks: a) Determine which color components your felt-tip pen color splits into. b) Determine which color component of your pen dissolves best in water and which one dissolves worst in water. Justify. e Fig. 1.31: Paper chromatography For testing purposes only - property of the publisher öbv

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