Prelaboratory Questions Name Laboratory Section 1. Read the Introduction and Procedure for this experiment, then answer the following ques- tions about preparing a TLC plate. a) Why must you hold the plate only by its edges? b) Why must you use a pencil and not a pen to draw the starting line that is 14 – ½ inch from the bottom end of the plate? c) Why must the starting pencil line be above the level of the solvent on the chamber? d) Why must the sample spot not be too concentrated?

Prelaboratory Questions Name Laboratory Section 1. Read the Introduction and Procedure for this experiment, then answer the following ques- tions about preparing a TLC plate. a) Why must you hold the plate only by its edges? b) Why must you use a pencil and not a pen to draw the starting line that is 14 – ½ inch from the bottom end of the plate? c) Why must the starting pencil line be above the level of the solvent on the chamber? d) Why must the sample spot not be too concentrated?

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...

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