What is the purpose of placing a filter paper inside a beaker or developing chamber for TLC? Among the three solvents used in the separation of pigments in spinach, which produced the most effective separation? Explain your choice using at most three sentences. a.hexane b.70:30 hexane:acetone c. 50:50 hexane:acetone

What is the purpose of placing a filter paper inside a beaker or developing chamber for TLC? Among the three solvents used in the separation of pigments in spinach, which produced the most effective separation? Explain your choice using at most three sentences. a.hexane b.70:30 hexane:acetone c. 50:50 hexane:acetone

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter34: Miscellaneous Separation Methods

Section: Chapter Questions

Problem 34.20QAP

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2. When separating acetone (an organic liquid) from LiBr (a solid impurity), which would be the most convenient means of separation? a. steam distillation b. column chromatography c. fractional distillation d. simple distillation Your answer:
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Flavonols are a type of flavonoids, in a silica gel stationary phase chromatography, with what kind of intermolecular force do the functional groups of the molecule interact with the silane groups? a. hydrogen bond b. van der Walls force ionic bond C. d. ion-dipole Which of the following compounds would elute faster on a reverse phase chromatographic column? a. beta carotene b. limonene c. quercetin d. Tocopherol
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What compounds present in a sample that can cause error in the analysis and alter desired results? A. Matrix B. Selectivity C. Analyte D. Interference
Which statement about TLC analyses is not true? * A- The line at the base of the TLC plate should be drawn with a pencil. B- To prevent contamination, a new capillary tube should be used to apply each sample. C- Samples should be applied multiple times in the same place to increase the concentrations of any possible compounds in the spot. D- A glass beaker lined with filter paper can be used as a development chamber in a TLC analysis. E- All these statements are correct.
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