The absorbance of the mixture was measured at 30s (A1), 5min and 6min intervals. The value A2 was obtained by averaging the values of the 5th and 6th minute. b. Urea 750 ml of urea reagent 1 and 450ml of urea reagent 2 was pipetted into the same 1ml cuvette. Following that, 12ml of patient's sample was transferred into the cuvette. The absorbance of the mixture was measured at 30s (A1), 5min and 6min intervals.
Decomposition of Aspirin Studied with UV/Visible Absorption Spectroscopy Aims: To determine the concentration of salicylic acid, formed from the hydrolysis of Aspirin, at regular intervals using the UV/Visible Absorption Spectroscopy From the concentration of salicylic acid, concentration of Aspirin to be determined using an equation Calculate the rate constant of this reaction and its order from a plot of graph of ln(aspirin) vs time Discuss the overall flaws and improvements to the experiment Results: As per schedule1, 0.212g of aspirin was added to 50 ml boiling water to form salicylic acid in a 100 ml flask, of which 1 ml was then pipetted to a 50 ml volumetric flask at the 5th min. Following an ice bath, the solution was mixed
The buret is filled to a point above the "0" mL mark with NaOH solution. In order to fill the tip of the buret with liquid, the solution is drained out of the bottom until the meniscus lies between the "0" and "1" mL marks. The initial buret reading can now be recorded to the nearest 0.01 mL. If you have any doubts as to your ability to read the buret correctly, ask your instructor to check your initial reading. Standardization of NaOH solution Accurately weigh out a sample of approximately 0.3-0.4 g of primary standard potassium hydrogen phthalate, KHPh, which has been previously dried at 120°C.
The supernatant was assayed for SOD activity by following the inhibition of epinephrine auto-oxidation. 0.5ml of sample was diluted with 0.5 ml of distilled water, to this 0.25 ml ethanol, 0.5 ml of chloroform (all reagents chilled) was added. The mixture was shaken for 1 min and centrifuged at 2000 rpm for 20 min. The enzymatic activity in supernatant was determined. To 0.05 ml of carbonate buffer (0.05 M, pH 10.2) and 0.5 ml of EDTA (0.49 M) was added.
The purpose of this experiment is to analyze the P content in a wastewater sample and to test the efficiency of 2 different methods for P removal from wastewater. To analyze the P content in a wastewater sample, standard P solution is made and calibration curve is generated and phosphate concentration in wastewater is determined by using calibration curve that is generated. To determine the concentration of P, vanadomolybdophosphoric acid spectrophotometric method is used. The predominating form of phosphate is dependent on pH. H₃PO₄ ⇌ H₂PO₄⁻ + H⁺ pKₐ=2.12 H₂PO₄⁻ ⇌ HPO₄²⁻ + H⁺ pKₐ=7.25 HPO₄²⁻ ⇌ PO₄³⁻ + H⁺ pKₐ=12.7 This method is under the acidic condition and ammonium molybdate is reacted with phosphate, then, the product reacts
Referring to Table 1, the reactants for each run were transferred to an Erlenmeyer Flask (250 mL) via a buret. Using a precision pipette, the volume of I3- required for each run was carefully extracted and poured into the flask containing all of the reactants. Immediately after the Iodine solution was placed in the flask, the LabQuest began collection data. Meanwhile, a small portion of the solution, was used to rinse the cuvette, then using a disposable pipette a small amount of the solution was transferred to the cuvette (approx. ¾).
The NaH2PO4 and Na2HPO4 powdered were weighted by using weighing machine, followed the mass that has been calculated in step (3). The NaH2PO4 and Na2HPO4 powdered were mix in a 500 mL beaker. 500 mL of distilled water were measured by using a 500 mL measuring cylinder, then is poured inside the 500 mL beaker containing both the powdered. The mixture were stirred by using a glass rod until the mixture is fully dissolved. The solution were tested by using calibrated pH meter to get the pH value of the solution.
NOTE: Record the grams of gasoline, kerosene, and lubricating oils that are present in the 50 mL of crude oil. ➢ Select the flask, and choose Heating Mantel option afterward select Max Heat and make sure you record the temperature when you see crude oil begins to boil. ➢ When the crude oil begins to boil, Make sure you turn the temperature down to 60% by decreasing the heating metal two times. Step 3: Record the
H and S were diluted 20x and P1 and P2 were diluted 2x to make up a total volume of 1ml each. 50ul of each diluted sample was pipetted into 8 wells of the microplate and 50ul of each protein standard was pipetted into 2 wells. 50ul were incubated with 50ul of alkaline copper reagent. 50ul of alkaline copper reagent was added to every well containing water, buffer, sample or standard and was incubated for 30 minutes. 100ul of Folin reagent was added to the wells and incubated for another 20 minutes.
Metal chelating activity Briefly, 2 mM FeCl2 was added to different concentrations of test sample and reaction was initiated by the addition of 5 mM ferrozine. The mixture was vigorously shaken and left to stand at room temperature for 10 min. Absorbance was measured at 562 nm after 10 min.8 % Inhibition = [(AB - AA)/AB] x 100, where AB, absorption of blank sample, AA, absorption of test sample. 2.6. Antibacterial