Salicylate Synthesis Lab Report

With these absorbance numbers a concentration curve was constructed and the unknown solution was determined by finding the point of absorbance on the curve.

10 microliters of the sample is then added and the assay absorption is measured at 340nm. If absorbance was above 1.5, samples were diluted.

2.What other factors did you need to control during your investigation? Explain how you controlled each one in your procedure.

0.1 gram of salicylic acid was weighed in a tray and was then added to a test tube containing 2.0 mL of Iron (III) chloride, which was measured using a 10 mL graduated cylinder, to test for phenols.

The first two questions will be answered during the introduction of the lesson and the rest will be the laboratory analysis questions. These will get the students to analyze and make sense of their lab results.

The compiled data was used to form population A of the experiment, while population B was predetermined and provided by the instructor. Research was conducted using primary sources and data collected in order to locate evidence supporting the hypotheses.

1) Discuss how your choice of equipment and how it affected the accuracy of your method. Discuss good volumetric technique.

The absorbance with SDS shows a rapid increase, before the graph begins to increase more slowly and uniformly. The absorbance levels off at 0.3nm. The absorbance with no SDS remains at a constant level of 0.1nm for the entire experiment. The absorbance of the control solution is also constant throughout the experiment. This shows the absorbance of the compounds in the solution without the ovalbumin, by taking this figure away from the other recordings, it is possible to discover the absorbance for ovalbumin alone.

One substance that was higher was S-10, when it was compared to the control it was calculated to be 145%. The biggest difference was C-30, when this substance was compared to the control it was 239%.

Spectrophotometry examines that as red blood cells lyse, they do not diffract as much light, so the absorbance can be recorded using a spectrophotometer. The cells can be directly observed utilizing microscopy, and a turbidity test can also be used.

In the first part of the experiment, best absorbance range was measured to be from 0.1228 to 1.8053 where error value was near zero. Methylene blue solution with an absorbance 1.8053 may indicate problems with the accuracy of the detector (e.g., a photomultiplier) .Since the detector system examines the transmitted light of the cuvette, the absorbance is calculated from this value. When transferring the linear transmission unit to the logarithmic absorbance unit, the accuracy is exponentially reduced with rising values. Based on the result obtained from part I, analytes in part II were diluted in 1:20 or 1:10 to generate absorbances that were within this range. Compared to theoretical Ctotal calculated from solution preparation in the second

Chewing wax, parafilm, teflon, rubber bands, and chewing gum are considered mechanical methods of stimulating salvia. Lemon drops or citric acid can be used to produce a tasteful stimulation of salvia production (Crouch, 2005). Following stimulation, salvia can be spit, suctioned, absorbed, or swabbed for collection. Some methods combine salvia stimulation with collection by using absorbent materials such as cotton balls or cotton rolls (Crouch, 2005). After the material becomes saturated, the device is removed from the mouth, and the oral fluid is reclaimed by centrifugation (Crouch, 2005). An example of an oral fluid testing instrument is Drugwipe, an immunochromatographic test strip based on the Boehringer Mannheim urine strip (de la Torre et al., 2002). Each class of drugs required a different device be used with Drugwipe. It was designed to be read visually, but poor lighting can lead to difficult readout. Due to this reason, the Drugread was developed to be used instead. This device had a similar color readout to the Drugwipe, but the Drugread also translated colors into a numeric value between 300-2500 (de la Torre et al.,

This was done by using SpectroVis and graphical analysis during and after the lab. The lab began by creating a dilute stock solution known as C. This was done by mixing stock solution in a serological pipet and diluting it with DI water. Proceeding this step, solution C was carefully poured into a cuvette followed by solutions A, B, D, E, and nondiluted stock that were obtained from other groups. After all the solutions were obtained, including an additional a cuvette of DI water, the SpectroVis was calibrated. This was done using DI water and was in order to select the correct wavelength, which was determined to be 529 nm. Then after the SpectroVis was calibrated, the nondiluted stock solution was put in the SpectroVis and the data began to be collected. Solutions A-E were then put in the SpectroVis and their absorbance was collected. Finally the unknown cuvette was put in the SpectroVis and its absorbance was recorded which concluded creating the calibration curve. After this then the SpectroVis was reset and a cuvette of sodium hydroxide was put in the SpectroVis for about 16 minutes. Following the completion of this step that portion of the lab was complete. After the lab was cleaned up and all the data was obtained, the data was then put into excel to make 4 different graphs, absorbance vs. concentration, absorbance vs. time, ln absorbance vs time, and 1/absorbance vs time. These graphs were used in order to find their slope which allowed to help find x and k. By using x, k, and the data obtained the rate law was able to be determined. By finding the rate law the purpose of the lab was

Table 1.0: Information gathered during the trial: The volume of KOH(aq),titrant, used in different trial.

The process of evaluating the absorbed MB used can be improved and made more precise by using titration.