The spectrometer was calibrated using a “blank” cuvette of methanol and then the absorbance and the wavelength for each dye was measured. Each dye was diluted tenfold several times with methanol until the max wavelength peak had an absorbance less than 1. All three dyes needed to be diluted 3 times before they were at the correct concentration to measure the maximum wavelength. As each dye was diluted the colors of the dyes became more faded and also a lighter shade, for example 1-1’-diethyl-2-2’-cyanine iodide, which was red initially became a shade of pink. The initial colors observed for pinacyanol chloride was blue and 1-1’-diethyl-2-2’-dicarbocyanine iodide was green. Graphs of the absorbance versus wavelength (nm) for all three dyes
The concentrations and absorbances of the red and blue dyes were used to find the concentration of the purple dyes. From the graph of the blue dye, the linear equation for absorbance was y = mx + b. From that formula came the equation y = 7.915 x 104 (x) + 0.02489, where y represents absorbance, m is slope, x is concentration/molarity, and b is the constant/y-intercept. The same set up was performed for the red dye, but the equation produced was y = 1.045 x 104 (x) +.001298. The equations found when graphing absorbance vs. concentration were used to find the concentration of the purple dyes. The absorbance for purple dye 3 on the red wavelength of 470 nm equaled 0.149 and 0.818 for the blue wavelength of 635 nm. For purple dye 1
From this graph and chart we can see that the higher the concentration the higher the absorbance, all the different concentrations were tested at the same wavelength (625nm). Also we can determine our unknown substances concentration by using the absorbance we got for it. The red dot on the graph followed by the line towards the horizontal axis indicates that the concentration of fast green was 34% or 5.1x10-3.
The purpose of this experiment was to determine the relationship between tail spine length and hemoglobin levels as well as the relationship between tail spine length and heart rate. The concentration of the hemoglobin in Daphnia is dependent on the oxygen available to them.
For this experiment, the amounts of Red 40 and Blue 1 were quantified in six different Kool-Aid samples through the use of a spectrophotometer. This was completing by performing serial dilutions on both dyes, Red 40 and Blue 1, and then creating calibration curves for each of the six samples. The absorbance and maximum wavelength values were obtained from the spectrophotometer for each individual drink sample. Beer’s Law was used to discover the concentration of
Scientists use an instrument called a spectrometer to quantitatively determine the amount of light absorbed by a solution. The primary inner parts of a typical spectrometer are described below. The spectrometer has a light source that emits white light containing a vast mixture of different wavelengths of electromagnetic radiation. The wavelength of interest is then selected using a monochromator (“mono” meaning one and “chromate” meaning color) and an additional exit slit. The separation of white light into different colors (wavelengths) is known as diffraction. The selected light then reaches the sample and depending on how the light interacts with the chemical compound of interest, some of the light is absorbed and some passes straight through. By comparing the amount of light entering the sample (P0) with the amount of light reaching the detector (P), the spectrometer is able to tell how much light is absorbed by the sample.
Introduction This experiment was undertaken in order to create stilbene dibromide. Bromine is added through electrophilic addition in attacking the double bond. This experiment was also executed to determine the stereochemistry of this addition reaction, whether it created meso products or d,l products. Data and Results Initially, 0.9 grams of stilbene were added to the solution.
In order to generate a bicyclic lactone in this experiment, a Diels-Alder adduct was produced. The bicyclic lactone to be generated was cis-1,3,3a,4,5,7a-Hexahydro-5-methyl-3-oxo-4-isobenzofuran-carboxylic Acid and was produced using a Diels-Alder reaction. The product was also analyzed quantitatively using percent yield. To prepare the Diels-Alder adduct 0.40 g of 2,4-hexadien-1-ol was added to a flask, then 5.00 mL of toluene and 0.40 g of maleic anhydride were added to the flask in that order. The mixture was warmed and stirred to induce a reaction. The reaction progress was monitored using a TLC plate with 30:70 hexane used as the mobile phase and silica gel as the stationary phase. The TLC plate revealed a new spot for the crude product, indicating the reaction had begun.
The dark, navy blue colored graph represented the absorbance curve for the S1 sample. The red colored graph represented the absorbance curve for the S2 sample. The green colored graph represented the absorbance curve for the P1 sample. The purple colored graph represented the absorbance curve for the P2 sample. The gaps between the P2 curve was due to the oversaturation that led to the inconclusive spectrophotometer readings. The blue colored graph represented the absorbance curve for the P1 low salt sample. The orange colored graph represented the absorbance curve for the P2 low salt sample. The light blue colored graph represented the absorbance curve for the P1 medium salt sample. The light pink colored graph represented the absorbance curve for the P2 medium salt sample. The light green colored graph represented the absorbance curve for the P1 high salt sample. The light purple colored graph represented the absorbance curve for the P2 high salt
Fast Green is used for specific staining procedures, for example protein, where is it used to better illustrate the presence of histones through a marker dye. For this part the experiment, the objective is to achieve the concentration curve of five known concentrations to find the unknown concentration through Beer-Lamberts Law. The concentration curve is also known as the calibration curve, both involve a graph with the concentration variables on the abscissae and the absorbance numbers on the ordinate. The absorbance spectrum of the Fast Green solution must be determined before obtaining the concentration curve. The maximum absorbance of the solution must be determined through the absorbance spectrum. The wavelength at the maximum absorbance was used to determine the absorbance for the diluted Fast Green
3. The spectrophotometer was set at 420nm. Distilled water was also used as the ‘blank’.
2-methylmercapto-4,5-dihydroimidazole hydroiodide was synthesized imidazolidine-2-thione by reaction with methyl iodide and this compound was used as the starting material. 2-alkylamino-imidazolines was obtained from the nucleophilic substitution reaction with 2-methylmercapto-4,5-dihydroimidazol hidroiyodür and different aliphatic amine such as, diamine, triamine and tetramine. The syntheses of the salts of these compounds were prepared from the reaction of the 2-alkylaminoimidazolines and various organic acids such as, succinic acid, picric acid, fumaric acid and phthalic
Iodine-131 is a radioactive isotope of iodine. It has half-life of 8 days, which means after 8 days it will decay to half of its original amount. Assume that you have a sealed box contains exactly 100 atoms of Iodine-131. Question: After 8 days, how many Iodine-131 atoms will remain intact (not decayed)
8) Steps 1 - 8 were repeated using the wavelengths of 360 nm to 900
concentration, record the absorbance readings at a fixed wavelength, and plot the absorbance vs. concentration data. The wavelength of 520 nm was selected for experiment Part
1. To speculate range of absorbed and reflected wavelength of light by Ruthenium-based dye based on its colour