TLC solutitions 2024

Precautions to take when spotting, developing and visualizing correct answersUse pencil to draw the line, do not flake the absorbant off because then the solvent will not rise up to the plate effectively, don't touch with nails, look for gauges. Oil on fingers will smudge the results. Why should bores of capillaries be small? correct answersSo that the spots made are as small as possible (less than .5mm in diameter) What are typical characteristics for solvents used as eluents correct answersIn general, the solvents for TLC and Column chromatography are characterized by low boiling points that allow them to be easily evaporated and low viscosities that allow them to migrate rapidly Characteristics of solvents used with respect to samples correct answersDepends on the polarity of the sample, polar solvent will move the samples higher up than non polar solvents Characteristics of solvents that allow them to migrate rapidly? correct answerslow viscosities Adsorbent materials and specific uses (what kind of adsorbents would be better for what kind of substances) correct answersA less active stationary phase like silica would be used for the more polar substrates, whereas a more active stationary phase (which will absorb substances strongly) like alumina is the choice for the separation of relatively non-polar substrates Uses of TLC and how it is used- all 6 correct answers(1) Determine number of components in a mixture (2) determine identity of 2 substances (3) monitor the progress of a reaction (4) determine effectiveness of purification (5) determine appropriate conditions for column chromatography separation (6) monitor column chromatography Effects of using too polar or too nonpolar a solvent correct answersToo polar will have all the spots move to the top of the TLC place and too non-polar will have all the spots stay at the bottom of the plate Visualization techniques - why certain kind of visualization technique was used for certain types of compounds correct answersUV- used for conjugated compounds I2 vapor- for most compounds