19. What is thin layer chromatography (TLC) LEAST useful for from the list below? A) To determine if crystallization or distillation may be more effective for a separation B) To determine the number of components in a mixture C) To determine the appropriate solvent for column- chromatographic separation D) To monitor the progress of an organic synthesis reaction

19. What is thin layer chromatography (TLC) LEAST useful for from the list below? A) To determine if crystallization or distillation may be more effective for a separation B) To determine the number of components in a mixture C) To determine the appropriate solvent for column- chromatographic separation D) To monitor the progress of an organic synthesis reaction

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

See similar textbooks

Similar questions

Paper Chromatography and TLC are examples of planar chromatography. True or FalsE?
Why is distillation of cyclohexanol using acid catalyst phosphoric acid a better technique to purofy rather than extraction, recrystallization, chromatography, IR spectroscopy?
The concentration of methylene blue in the sample is estimated through (select the correct) options: refractive index measurement (refractometry). turbidity measurement (turbidimetry). absorbance measurement (spectrophotometry). titration with 2% HCl solution.
Classify the descriptions based on whether they apply to ion‑exchange, size‑exclusion, or both types of chromatography columns. - Proteins move through the column at rates determined by their net charge. - The gel bed will contain polymer beads with charged functional groups. - Proteins move through the column at rates determined by their size. - The gel bed will contain porous polymer beads. - The properties of the proteins affect the rate at which they migrate. - Proteins are separated based on differences in their amino acid sequences.
Which is correct? Random errors affect accuracy and systematic errors affect precision. An accurate result shows agreement with the true or accepted value. Precise results can contain significant random error, but little systematic error. The standard deviation is a good measure of accuracy. Polydimethylsiloxane (PDMS) stationary phases have low polarities. Which of the following statements is TRUE about gas chromatography using PDMS stationary phases? The gas chromatography column is typically packed with silica microparticles. An oven is used to control the column temperature because a constant temperature is always needed in gas chromatography Octane (C8H18, boiling point: 126 ºC) is eluted later than dodecane (C12H26, boiling point: 216 ºC) 3-Pentanone ((C2H5)2CO, boiling point: 102 ºC) is eluted later than propanol (CH3CH2CH2OH, boiling point: 97 ºC)
Identify the detectors in gas chromatography that can be used for the detection of each type of analyte. More than one detector may be appropriate for a given analyte, and a given detector may be appropriate for more than one type of analyte. compounds ionized by UV radiation sulfur or nitrogen containing compounds halogenated compounds flame ionization Answer Bank mass spectrometer nitrogen and phosphorous containing compounds thermal conductivity electrolytic conductivity hydrocarbons electron capture thermionic photoionization
A young researcher set out to develop a method for quantifying the polycyclic aromatic hydrocarbon (PAH) content in a contaminated soil sample using open tubular gas chromatography. During the initial stages of method development, the researcher was unable to separate the early eluting compounds, anthracene and naphthalene, with baseline resolution. Select the possible modifications the researcher could make to improve the resolution. use a column with a smaller inner diameter decrease the column length increase the stationary phase thickness increase the temperature choose a different stationary phase
thin layer chromatography: What would happen to the Rf value of a compound if you increased the polarity of the mobile phase while using a polar stationary phase? please help me this question! Thank you a lot
2. A gas chromatogram of a four-(4)-component mixture had the following areas and retention times (RT). Component ABCD (RT) (min) 2.564 5.241 1.904 3.217 Area (mm²) 2341 1278 4302 1987 A. Which compound do you suspect is the most volatile? Why? B. Calculate the percent composition of component D.
You are analyzing the volatile liquids in charcoal lighter fluid. Which type of chromatography would be the best choice? Ion Exchange Thin Layer Gas HP Liquid Size Exclusion
QUESTION 3 What is one disadvantage of using column chromatography? It is relatively ineffective at separating most organic compounds The desired compound must be the ≥95% majority compound in the initial mixture for a column to be effective It is only effective at separating room temperature gasses It wastes a significant amount of solvent