Question

looking for a check of my work, is this correct? if not please let me know. thanks!

1. (23 Total Points) Gas Chromatography a. (5 pts) Circle the BEST answer for the question below. Of the compounds listed below, which would you expect to eluto last from a nonpolar gas chromatographic column? 3 • n-Propanol (CH3CH2CH2OH) Polar Polar = 7* (mPoland 1. Methanol (CH3OH) Polar NON-Polar = 2nd 4. n-Butanol (CH3CH2CH2CH2OH) ВР 1st Low C . n-Pentanol (CH3CH2CH2CH2CH2OH) and Higher 2. Ethanol (CH3CH2OH) lar Elution Provide a brief justification for your answer: All options Are Polar, so Would be BASED ON Boiling point. More carbons = Higher BP = So in pentang has the most amount of (Arbons AND HAS the Highest BP AND will Elute the latest / IASH BP & Polarity b. (6 pts.) Explain what the retention time of a species tells you about the compound traveling through a given GC column. For example: If you have a chromatogram with two peaks corresponding to Compound 1 (CI) & Compound 2 (C2), then what does it mean for the retention time of C1 to be less than C2? Retention time can determine the Baling oint AND Polarity of A Compound. If compound 1 is less than Compound 2 then it may Mean it has a lower Be or it is more Polar (If in Non-Polar GC) (Nice versa if in A Polar GOL

Answer 1

Your answer is rights. I think In addition to boiling point & polarity you can also consider Van der waal forces here which increses with increase in surface area of molecule & results into the increasing adsorption tendency.