Beer's Law Lab Report

Lab #1
Beer’s Law

Stephanie Redmond
Tuesdays 11 am – 1:50 pm
Lab partner: Guilherme Bueno Dorea
RESULTS
Part One (Figure 1) (Figure 2) (Figure 3)

(Figure 4) For part one of the lab, a Vernier SpectroVis Spectrometer was used to determine what type of olive oil was being analyzed. The grade of olive oil is determined by how the oil is extracted which also determines how much chlorophyll is left in the oil. These varying amounts of chlorophyll allow for the identification of the grade through spectrometry as the chlorophyll leaves distinct peaks in both the blue and yellow-red ranges. As shown in the figures above, different grades left peaks at different wavelengths and absorbencies. To determine the grade of the unknown

Discussion The two most helpful features of the spectra to determine the unknown olive oil were wavelength and absorbancy. Also, the physical color of the olive oil was a very helpful indicator of the grade. Based on all of these facts, the unknown sample of oil was definitely extra virgin grade. It had both a dark yellow color similar to the extra virgin reference as well as a similar absorbancy peak. Based on the references take, a mixture of extra virgin and light olive oils would most likely have features resembling regular olive oil. It would have a lighter but still bright yellow color, and a wavelength and absorbancy between the ranges for extra virgin and light olive oil. Without the use of a spectrometer, the concentration of an unknown solution of nickel (II) nitrate could be estimated based on the coloring. The more concentrated the solution the darker green in appears and, vise versa, the less concentrated the lighter the solution will become as it is diluted by water. You could use Beer’s Law to calculate the unknown concentration of cobalt (II) nitrate as Beer’s Law states that a solutions concentration is proportional to the solutions concentration. Based on this, if you had the equation for Beer’s Law you could then plug in the unknown solutions absorbancy at 750 nm to find the