Bromopanol Vs Bromophenol

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

The determination of the number of thiol groups by DTNB is carried out at pH> 7.5 because the extinction coefficient is strongly pH dependent at pH values more acidic than 7.5. With an altered pH the maximal extinction may be altered, meaning that the absorbency figures will be

After the serial dilutions of the red and blue dyes were taken, the molarity and absorbance for both dyes were calculated. Using the MiVi = MfVf equation, the concentrations for each value of the red and blue dye were separately calculated. Calculating absorbances calls for setting the correct wavelengths of light for each dye. In this case, the 470 nm wavelength for red dye and the 635 nm wavelength for blue dye was needed to find the maximum absorbances. The absorbance was found by blanking the colorimeter and entering the concentrations. After both values of the absorbances and concentrations were found, the values were then graphed in order to obtain the equation of the relationship between absorbance and concentration.

The isosbestic point of the acid (pH6) and basic forms (pH10) of para Nitrophenol (PNP) was expected at 350nm. As you can see in figure 2, the graph shows the intersection of 2 curves at ~350nm, which is matched with the literature value. Also, the pKa of PNP was expected 7.15 at room temperature. Refer to figure 3, the pKa is estimated to be 7.15-7.2, which very close to the literature value. In addition, the lab was succeeded in illustrating the use of a spectrophotometry to analyze concentrations of chemical substance. The absorbances of 2 unknowns were felt on the standard curve as the expectation (refer to table 4). The minimum absorbance of the known standards was 0.193 and the maximum is 1.830. The absorbance of the unknown

Spectrophotometers are quite precise instruments allowing for five significant figures to be obtained. The major source of error in this lab is how small the concentration of the reagents are.

Introduction: The goal or purpose of this experiment was to determine the concentration of Allura Red in red commercially available beverage- Gatorade. Colorimeter are used to shine a LED light through the solution and hit a photocell: it will detect an absorbance or a percent transmittance value. These “value” can be charted and examined as a calibration curve. Calibration curve is a method for determining a substance concentration in an unknown sample

Design an experiment to test whether compound X can function as an inhibitor of bromelain. Be sure to identify any controls that must be included as well as your independent variable.

In this experiment 10 cuvettes were filled with the appropriate dilution, an additional cuvette should be filled with distilled water which should be used to calibrate the colorimeter. Record the absorbance and transmittance for each dilution generated from the Webquest. Additionally, two samples of Gatorade contains Blue Dye #1 (Low Calorie and Glacial Frost) were tested and found that the Low Calorie Gatorade had an absorbance of .135 and the absorbance of the Glacial Frost Gatorade was .153. Using linear regression the concentration of the two samples can be found if the value of transmittance is substituted for the Y value. The concentration of sample 1 is 62.8 µM and the concentration of sample 2 is 69.68 µM respectively reporting in four significant

Incorporation of assay controls included setting up a spectrophotomer and running the chart recorder with a full-scale deflection before the start of the assay. The set recorder had a corresponding value of 1 for the change in the absorbance. Therefore, prior testing was done to observe whether a change occurred in the readings. This helped to indicate that the results were valid, as they could have been affected by a fault during the setting up of the spectrophotometer. On the other hand this was considered as one of the controls for the experiment. Nevertheless, a new cuvette had to be used for each assay.

By using acid-base titration, we determined the suitability of phenolphthalein and methyl red as acid base indicators. We found that the equivalence point of the titration of hydrochloric acid with sodium hydroxide was not within the ph range of phenolphthalein's color range. The titration of acetic acid with sodium hydroxide resulted in an equivalence point out of the range of methyl red. And the titration of ammonia with hydrochloric acid had an equivalence point that was also out of the range of phenolphthalein.. The methyl red indicator and the phenolphthalein indicator were unsuitable because their pH ranges for their color changes did not cover the equivalence points of the trials in which they were used. However, the

Colorimetric assay is a process of determining a concentration of a solution based on absorbance of light. The purpose of this lab is to determine if the Bradford assay is an accurate way to determine an unknown concentration of two samples of protein. The Bradford assay is done by measuring wavelength of light passing through a cuvette filled with Bradford dye and concentrations of PBS and proteins. After the cuvettes are mixed they are placed into a spectrophotometer to measure wavelength. The wavelength given will be used to plot a standard curve based on concentration (x-axis) and wavelength (y-axis). The standard curve is then used to measure an educated guess on the concentrations of unknown protein concentrations. We hypothesized that if we use the Bradford assay and colorimetric spectrophotometry we can determine an accurate concentration of two unknown concentrations of proteins. The results of this lab failed to reject our hypothesis based on accurate measurements of protein concentrations. The standard curves are drawn with a linear increasing slope. The Bradford assay is an accurate way to demine the concentration of an unknown concentration.

The absorbance is measured using a Plate reader and a Standard curve is generated. Also, the different types of pipetting techniques are assessed in this Assay.

The purpose of this experiment was to determine the pKa of the bromothymol blue (indicator) through absorption spectroscopy. Bromothymol blue being a monoprotic acid base indicator, displays different colors at different pH because of the differences in the ratio of the conjugated acid and base form. The fraction of conjugate acid and base was interpolated for the solutions through the acquired absorbance spectrum of the bromothymol blue at various pH. The rearranged form of Henderson Hasselbalch equation was graphed as a function of pH to determine the pKa of the indicator.

Purpose: To use indicators to test for the presence of organic compounds in certain substances.

Polychlorinated biphenyls are mixtures of up to 209 individual chlorinated compounds (known as congeners). There are no known natural sources of PCBs. PCBs are either oily liquids or solids that are colorless to light yellow. Some PCBs can exist as a vapor in air. PCBs have no known smell or taste. Many commercial PCB mixtures are known in the U.S. by the trade name Aroclor.PCBs have been used as coolants and lubricants in transformers, capacitors, and other electrical equipment because they don't burn easily and are good insulators. The manufacture of PCBs was stopped in the U.S. in 1977 because of evidence they build up in the environment and can cause harmful health effects. Products made before 1977 that may contain PCBs include old fluorescent