Question

question #2 please

Reverse phase chromatography is the most common type of liquid chromatography which the solid phase is made up of a packing material that is largely hydrophobic and the eluents are of varying polarities. In general, the more polar compounds elute first from the column followed by more hydrophobic compounds. PRELAB QUESTIONS 1. Draw structures for the following analytes for the simulation: a. acetophenone b. benzophenone c. butylparaben d. propiopheneone e. ethylparaben f. propylparaben g. ketoprofen h. 3-nitrophenol i. 4-nitrophenol 2. Put the analytes in order of increasing hydrophobicity. Which of the compounds is most hydrophilic? Which is most hydrophobic? What is the predicted elution order from a reverse phase chromatography column? 3. Go to http://www.hplcsimulator.org/ and download the simulator or use the computers in Lab (TBD) where the software has been installed. NOTE: You may need to update or activate Java if it is out of date on your personal equipment. DURE pen the HPLC Simulator. Under the graph are two buttons “autoscale" and "pan". -th should be on. On the left side is a panel that allows you to set and change ameters. Set the following initial parameters for your simulation:

Answer 1

2002 Acetophenone Benzophenone OH Butylparaben Propiophenone ОН Ethylparaben O-H OH OH Ketoprofen Oo 4-Nitrophenol Propylparaben 3- Nitrophenol Hydrophobic literally means "the fear of water". A hydrophilic literally means attract of water molecules and tends to be dissolved by water. Increasing order of hydrophobic nature 3-Nitrophenol Ethylparaben Butylparaben Propiophenone Ketoprofen 4-Nitrophenol Propylparaben Acetophenone Benzophenone Decreasing order of hydrophilic nature Carboxylic acids > Phenols > Esters > Ketones Note: Hydrophobic nature increases alkyl group size increases. In reverse phase chromotography, more polar compound comes first. Comes first Comes last 3-Nitrophenol Ethylparaben Butylparaben Ketoprofen Propiophenone 4-Nitrophenol Propylparaben Aceto phenone Most polar Least polar Most hydrophilic Most hydrophobic