EXPERIM ENT: PREPARA TIV E GAS CHRO M A T O GRAPH YName _______________________________________ Instructor ____________________________________ Chem ____________ Section/Color ______________Date ________________________________________ Laboratory QuestionsThese questions are to be completed and turned in with the Laboratory Report. POST-L AB QUESTIONS1.The stationary phase in gas chromatography of organic molecules is normally classified as a liquid phase. However, if we remove the packing material from one of our GC columns, it would come out of the column looking like very finely divided sand. Explain why our liquid phase 'looks' like a solid. (Read the Techniques section of the lab manual. Hint: What is placed in the column besides the material used as the ‘liquid phase’?) 2.Why is it possible to separate some compounds with identical boiling points by gas chromatography even though they cannot be separated at all by distillation, even fractional distillation? 3.Explain the direction in which the retention time would change (longer or shorter) for a substance in a GC experiment when the experimental parameters are changed as shown below.
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