It is understood that large polarizable ions (i.e. the Iodine in NaI) tend to collect near the air/water interface whereas smaller less polarizable ions (i.e. the Fluoride in NaF) tend to collect near the bulk of the liquid. This has been shown using electron spectroscopy; however, it is our goal to show this using ellipsometry. We would also like to determine the concentrations at which these behaviors begin to occur. It is our hypothesis that sodium iodide, NaI, will need a very low concentration to detect little or no ions at the air/water interface. On the other hand, sodium fluoride, NaF, will need a very high concentration to detect any ions at the air/water interface. Finally, it appears that sodium iodide is light sensitive. If time allows, I would like to check this theory by performing a 24 hour experiment to see if the amount of time the solution is exposed to light makes a difference in our data.