Definition & History of Thin layer chromatography

Definition & History of Thin layer chromatography Thin layer chromatography (TLC) or planer chromatography, began as a method of separating mixtures by eluting them through a planner chromatographic bed theh visualizing the separated components by staining or charting. For the first time Beyerinck in 1889 and Wijsmann in 1896 worked on TLC. After that lzmailow and Shraiber in l938 gave the ideas and fundamental principles ...

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Advantages & Disadvantages of Paper Chromatography

ADVANTAGES OF PAPER CHROMATOGRAPHY 1. One of the major advantages of paper chromatography is the sensitivity with which compounds can be located after separation. Amounts as little as 0.1 microgram (one micrograms is one millionth of a gram) of some compounds can be detected with routine reagents. 2. The operation time is small. DISADVANTAGES OF PAPER CHROMATOGRAPHY 1. Paper chromatographic techniques can not ...

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APPLICATIONS OF PAPER CHROMATOGRAPHY The literature on analytical methods and on the investigation of compounds shows that there are hardly any fields in which paper chromatography has not found some use. it is very much used as a research tool. It is also being used increasingly for routine analyses particularly for new separations where no classical method exists. Some of the principal uses of ...

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Chemical & Physical methods to locate spots in Paper Chromatography

LOCATION OF THE SPOTS After drying of the developed chromatograph, it is very essential to locate the separated substances. If the substances are coloured, no difficulty arises but the problem stands with the colourless substances. There are several methods which have been described to locate the spots, all of which can be grouped into 1 ) Chemical and (2) Physical methods. CHEMICAL METHODS ...

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Horizontal or Circular Chromatography Technique

HORIZONTAL OR CIRCULAR CHROMATOGRAPHY This technique is developed by Rutted. He used a circular piece of filler paper with a wick cut parallel to the radius from edge to center. The sample is applied at the centre of the paper with upper end of the wick. The paper is laid down between two Petri dishes with the wick dipping into solvent mixture ...

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Two-dimensional chromatography

TWO DIMENSITIONAL TECHNIQUE When the mixture is complex and incomplete separation is obtained with one dimensional chromatography then two-way or two-dimensional chromatography in two different solvents is employed to produce better resolution of the component spots.In this method the solution is spotted in the corner of a square or rectangular sheet of paper. The ascending or descending chromatography is carried out. When this is ...

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Descending Method in Paper Chromatography

DESCENDING TECHNIQUE In this method, the developing solvent is placed in a trough made of an inert material such as glass. The trough is placed in the chromatographic shown in the figure.    

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Ascending Method in Paper Chromatography

ASCENDING METHOD This is the simplest of all the methods. The paper or strip is suspended vertically into a closed jar containing a suitable solvent)(mobile phase). taking care that the dried spot region remains above the solvent.The solvent ascends through the fibres of the paper by capillary action.The rate of ascend is slow and decreases with time because of gravity. In ...

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Development of Chromatogram in Paper Chromatography

Development of  Chromatogram in Paper Chromatography There are a number of apparatus designed to carry on paper chromatography. The following things are taken into consideration: 1. There is sufficient amount of solvent at the bottom of the reservoir. 2. There is proper arrangement so that the paper is freely suspended. 3. It is particularly to be noted that large temperature variations are ...

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Discuss Renaissance prose,who were its main authors?


  Renaissance – roughly 1485-1660 The most known/influential authors of Renaissance prose were: - Sir Francis Bacon o Essays o The Advancement of Learning o Novum Organum o New Atlantis - Richard Hooker o Laws of Ecclesiastical Polity - Sir Thomas More o Utopia - Sir Walter Raleigh o The Discovery of Guiana o The History of the World - ...

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