Introduction
When white light passes through a prism, it forms a continuous spectrum of colors found in the visible region of the electromagnetic spectrum. The color of the compound is a blend of wavelengths that are transmitted and not absorbed by the sample. Beer- Lambert’s Law is applied in order determine the concentration of a colored species in solution. The concentration of the colored species is directly proportional to it absorbance at a wavelength. A= εbc which A is the absorbance, ε is the molar absorptivity, b is the cell path length in cm, and c is the concentration of colored species it makes a straight line where y=mx+b (Patterson 2).
The Beer Lambert law which is applied to optics is named after Pierre Bouguer, Johann Heinrich
…show more content…
The Beer Lambert law delineates that there is a linear relationship which is present between the saturation of a solution and the luminescent absorption of a solution. In the circumstance of the existence of a linear correlation, the resulting graph should demonstrate to be a straight segment of a line. In the circumstance that the graph demonstrates a straight line, this would confirm the Beer lambert law. The experiment which has been conducted incorporates water combined with food coloring at diverse concentrations of the solution (Clark …show more content…
Initially the three colors which were implemented had been red 3, yellow 5, and green 3. A 10 mg% solution was created by taking .005 grams of red 3, yellow 5 and subsequently diluting to 50 ml water in a volumetric flask. Yellow 5 was assessed with an absorption level of 1.09 and wavelength of 359. Red possesses a wavelength of 360 and an absorbance of 1.084, and green 3 had demonstrated a wavelength of 620 with an absorption level of 1.464. For the commercial products mountain dew for yellow 5 it was diluted with 50 ml of water, green 3 with Listerine, and red sugar crystals for red 3. It was ground to measure it 1.0
There is a technique called polarimetry that uses polarized light and asymmetric carbons like those found in glucose. The amount of polaritization can be used to determine the amount of active molecules present in solution.3 The equation used is measured rotation of angle = (a)lc, (a) is optical activity, c is the concentration, and l is the pathlenght. The concept seems similar to Beers
The analyzed yellow#5 wavelength was determined to 395nm because the actual wavelength 427nm was restricted in the Micro lab. The R2 value of the graph is 0.9827, and the level of data accuracy it indicated extremely weak data correlation. The first one dilution data points excluded from the standard curve because the point is not in the linear curve. The first concentration and absorbance value are the highest point in the graph that cannot connect as linear with another data point. After removing the first data point, the standard curve is clear and make
Absorbance was defined as: log I_o/I where I_o is incident light and I is the transmitted light. Fluorescence emission spectrum is different from fluorescence excitation spectrum because it records different wavelengths of chemical s...
The purpose of conducting experiment was to determine the identity of white compound. Based on the 5 gram of unknown white compound several experiment conducted including solubility test, pH test, flame test, and ion test. Several materials including chemicals used throughout experiment and will be described through paragraphs.
...s the change in the temperature of both of these batches, 6°C for the pure, and 13°C for the crude. In this final sub-section of the Characterization of Aspirin, the values of absorbance were recorded. Initially, 0.0566 grams and 0.0590 grams of pure and crude Aspirin respectively were obtained and each individually placed into beakers (400 milliliter) and had 250.0 milliliters of distilled water added to them. From each beaker, a tiny amount of the just dissolved solutions was transferred to a cuvette, one cuvette for each type of aspirin. Each cuvette was placed into the ultraviolent spectroscopy mechanism which was connected to a computer and absorbance spectrum values were obtained at 298 nm (Figure 5) (0.1987 pure aspirin, and 0.9549 crude aspirin).
A low absorbency would have a low color change so would be clear or slightly clear by the end of the trails and a high absorbency would have a strong red color by the end of the experiment.
Using the spectrophotometer, the absorption of each sample was measured by scanning the wavelengths. After calibrating the spectrophotometer with the blank test tube, each sample was placed into the spectrophotometer and read at 360nm. Observations were continued for each pigment sample increasing the wavelength by 20nm increments. Once these absorbance values were recorded, absorption spectra for each pigment were graphed.
Potassium permanganate test is performed to see the presence of alcohol in this experiment. Five solutions were tested and out of all of them, aqueous methanol and solutions 4 and 6 changed color during the test, meaning that those solutions contained alcohol. Fresh aqueous aspartame and water do not contain alcohol, which is why we saw no color change. Solutions 4 and 6 were hydrolyzed aspartame and diet soda, respectively, under different conditions, and methanol is a product of hydrolysis.
The basic principle of the spectrophotometeric technique is the measurement of interaction between energy and electrons of the substance. Spectrophotometric technique is an analytical method used for estimating concentration of metal ion in liquid solution. One of the most magnificent effects of complex formation is the change of spectral properties. The reason for light absorption by complexes are as follows.
This is related in the following law, called Snell's Law: ni sin i = nr sin r. For red light in air hitting water this gives sin r = sin i/1.33
light hitting the cell by the ratio of area of the cell to the ratio
A cuvette was filled 3/ 4ths of the way and the absorbance measured in a spectrophotometer. The data was compiled as a class and recorded. The Spectrophotometer was blanked using a test tube of distilled water.
Masters, Barry R. "Albert Einstein and the Nature of Light." 2010. Optics and Photonics News. The Optical Society. Article. 31 March 2014. .
While investigating the use of fiber optic technology, it is important to understand the fundamental rules of optics. Some of the leading scientists of their time viewed light from two main perspectives.
The results obtained from the experiment supported the hypothesis. This was because as the distance increases the light intensity of the LED light decreases. The LED light phase 1 results strongly demonstrate that an incoherent light obeys the inverse square law under laboratory conditions and real-life situation. Figure 1 and 7 shows that the light intensity varies inversely with the square of the distance. Therefore, the results obtained from the experiment supported the hypothesis.