Absorbance

Each material was diluted with water and placed in a separate cuvette so that the spectrophotometer could accurately reveal the absorbance. The cuvette that was filled with water was used as a blank to zero out the spectrophotometer. Each cuvette was then inserted into the spectrophotometer to find the absorbance. The main goal of this week was to figure out the relationship between the wavelength of light absorbed and the color of a compound. Found on page 87 of lab manual, the absorption wavelength is related to the energy of the light that is absorbed by a molecule. The color of the light reveals information about the kind of molecule that does the absorbing. The amount of absorption is dependent on the type of molecule.3 Each of the cuvettes filled with the prepared solution was measured in wavelengths that ranged from 350 nanometers to 650 nanometers in 50 nanometer percentage increases. As seen in Figure 1, there are no trends in the absorbance rates of each solution used; however, the graph shows that the different wavelengths do have an effect on absorbance. As seen in Figure 2, the calibration curve of potassium permanganate reveals that as the concentration of KMnO4 increases, the absorbance also increases as the transmittance…

not change the performance of the chromogenic agent. The chromogenic reagent is the iron(III)-thiocyanate complex. Time Duration: The maximum wavelength of the complex was found to be approximately 470 nm. Since the complex had a reddish-brown color and the use of complementary colors, the measured absorbance was within the expected value for the visible blue region. For the time duration, physical observation of the samples showed a fading in the color of the complex as time progressed. As…

Through calculation, the percent transmittance allowed for the determination of absorbance. To zero-out the spectrophotometer, about 2/3 of the blank solution was poured into a cuvette and placed in the spectrophotometer device until it displayed 100% (allowed for the measurement of the absorbance of just the phosphate). The solution in the cuvette was disposed in a designated beaker, then it was thoroughly rinsed with distilled water and dried with Kimwipes. About 2/3 of the first solution was…

Rabia Iqbal Biol 395-1005 lab 01/31/2015 Broadford assay Absorbance Figure 1. The concentration and absorbance of Bradford assay. Four samples containing Bovine serum albumin, diluent, and Bradford. At 0.25 mg/ml concentration the absorbance was 0.109 nm and the relation between absorbance and the concentration held constant throughout except at the 0.50 mg/ml when the concentration absorbance was 0.186 nm. Figure showed that as the concentration is increased the absorbance elevates also. All…

Figure 1 shows the relationship between concentration and absorbance known as the Beer-Lambert law or calibration curve. The data from the made solutions in table 2 was used to create the graph. The graph has a linear trend line that predicts where a point would fall on the graph. The equation of the trend line is equation 7: y=0.9508x-0.0055 with a R2 value of 0.99943. This equation was used to find the true concentration of the made solutions as well as the unknown solution. The R2 value…

Part B: Change the amount of enzyme Table 4: The absorbances of 5 cuvettes that measured at 475nm during a given time interval using spectrophotometer. Time (s) Absorbance @ 475nm Cuvette 1 Cuvette 2 Cuvette 3 Cuvette 4 Cuvette 5 0 0.003 0.003 0.004 0.002 0.009 30 0.003 0.004 0.008 0.013 0.021 60 0.005 0.005 0.013 0.016 0.031 90 0.005 0.008 0.019 0.020 0.040 120 0.007 0.011 0.022 0.033 0.051 Figure 4: The graph of time vs. absorbance of 5 cuvettes that contained different amount…

Dilution range was made between 2mg/ml-300mg/ml of pectin in deionized water. FeSO4 standard consisting of 0.2, 0.4, 0.6, 0.8 and 1mM in deionized water was used to plot a standard curve, the activity of pectin was determined relative to 1mM of the standard. The stock solutions include 300mM acetate buffer, pH 3.6, 10mM TPTZ (2, 4, 6-tripyridyl-S-triazine) solution in 40 mM HCl and 20 mM Fecl3.6H2O. The working solution was prepared fresh by mixing 25 ml acetate buffer, 2.5 ml TPTZ and 2.5 ml…

prepared to measure the absorbance at lambda max and plot the results against the concentration of solution to generate a standard curve. Then it must be determined the amount of each flavor in a sample of the unknown by comparison to your standard curves. The ingredient in each flavor of the Kool-Aid that was tested is Blue 1 and Red 40. The Lambda max for red 40 is 503nm and for the blue 1 it is 629nm. A UV/Vis spectrophotometer was used to measure the absorbance of the Cherry, Berry Blue,…

concentration for each tube were as follows: 0.015 mg/ml for tube 1, 0.0075 mg/ml for tube 2, 0.00375 mg/ml for tube 3, 0.001875 mg/ml for tube 4, and 0.000935 mg/ml for tube 5. The absorption spectrum was performed for cuvette 1 to determine the maximum absorbance wavelength Figure 1. Cuvette #6, with 5ml of distilled water, acted as a blank to recalibrate the spectrophotometer to 0.000 absorbance between changing wavelengths.…

Shown in Figure 6, the absorbance/concentration at lambda max vs SPF once again shows a positive correlation, with the slope of the line being positively 0.1895. The pattern follows the absorbance vs SPF with the higher the absorbance/concentration, the higher the SPF value and the lower the absorbance the lower the SPF. Also Figure 8 has the same pattern, but the absorbance values correspond to a different wavelength. However, one very noticeable difference in the absorbance/concentration vs…