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HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

HPLC stands for High Performance Liquid Chromatography. This is an analytical chemistry technique that is used to separate, quantify and identify every component that is in a mixture. The technique depends on pumps to push some constrain liquid solvent which contains a mixture of the sample through a column containing a solid absorbent material. Each of the components in the sample will interact with the absorbent material in a slightly different way. This will cause different flow rates in the various components hence causing the components to separate as they flow out of the column. High Performance Liquid Chromatography is used mainly for manufacturing, medicine and research purposes. High Performance Liquid Chromatography is used in separating and purifying compounds according to their polarity. To understand polarity, we can use a simple example of oil, water and ethanol. Ethanol is polar. Thus it will mix properly with water. On the contrary, oil is not polar, so it does not ...
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Infrared Spectroscopy(IR)

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1)   What is the principle of IR? Infra-red spectroscopy is an important spectroscopy which gives almost complete information about the structure of a compound. The infra-red spectrum is containing a large number of absorption bands which provides much information about the molecule's structure.  2)    What is the range of IR? Region  Wavelength range (λm) Wave number range (cm-1)  Near 0.78 - 2.5 12800 - 4000 Middle  2.5 - 50 4000 - 200 Far  50 - 1000  200 - 10  The absorption of infrared radiations can be expresses either in terms of wavelength or wave number.  Wave length = 1/wave length (cm) The intensity of bands observed in IR spectrum is expressed in terms of transmittance (T) or absorbance (A). A = log10 (1/T) Because of absorption of infra-red radiation, molecu...
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Interview Question on Wet Chemistry

1)What is LOD test? Ans: The 'Loss on Drying' Test is designed to measure the amount of water and volatile matters in a sample when the sample is dried under specified conditions. 2)What do you mean by sulphated ash? Ans: The sulfated ash test utilizes a procedure to measure the amount of residual substance not volatilized from a sample when the sample is ignited in the presence of sulfuric acid. The test is usually used for determining the content of inorganic impurities in an organic substance. 3) What is the meaning of loss on drying? Ans: Loss on drying is a widely used test method to determine the moisture content of a sample, although occasionally it may refer to the loss of any volatile matter from the sample. The loss in drying does not usually refer to molecularly bound water or water of crystallization. 4) What is a vacuum drying oven? Ans: A vacuum drying oven...
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