Consider the TLC chromatogram shown below This is the developed TLC plate obtained by a student after spotting three (3) different compounds in each lane and running the TLC using a 70:30 hexane:ethyl acetate mobile phase. Which of the following can help the student improve his/her TLC analysis? Select all that apply. (Note: ethyl acetate is more polar than hexane) A. Increase the polarity of the mobile phase to achieve better separation. B. Decrease the amount of hexane and increase the amount of ethyl acetate in the mobile phase. C. Use 100% hexane as the mobile phase to achieve better separation. D. Decrease the polarity of the mobile phase since the compounds are relatively non-polar. E. The compounds are impure. Further recrystallization is needed.

Consider the TLC chromatogram shown below This is the developed TLC plate obtained by a student after spotting three (3) different compounds in each lane and running the TLC using a 70:30 hexane:ethyl acetate mobile phase. Which of the following can help the student improve his/her TLC analysis? Select all that apply. (Note: ethyl acetate is more polar than hexane) A. Increase the polarity of the mobile phase to achieve better separation. B. Decrease the amount of hexane and increase the amount of ethyl acetate in the mobile phase. C. Use 100% hexane as the mobile phase to achieve better separation. D. Decrease the polarity of the mobile phase since the compounds are relatively non-polar. E. The compounds are impure. Further recrystallization is needed.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter8: Sampling, Standardization, And Calibration

Section: Chapter Questions

Problem 8.16QAP

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