The same filling procedure above was used to fill the other wells, but with differing amounts of each solution. In Well #2, 1.5 mL of water and 1.5 mL of HCL was used. In Well #1, 0 mL of water and 3 mL of HCl was used. Once each well was filled, a stopwatch was prepared to time the reactions that would occur in the next steps. To begin the reactions, the “Na2S2O3” syringe was used to place 2 mL of Na2S2O3 into Well #1.
Note: make sure that you leave space between distillation take-off and the cylinder. This would allow you to observe the drops of the distillate that enter to Graduated Cylinder. Step 2: Begin distillation.
Do the same for the other test tubes. Let the test tubes not be disturbed for about 3- 4 mins. Then add the Amylase solution to the Starch solution and start the stopwatch (immediately). After every 1 min take one drop from the test tubes and place then in the test plate that were
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 sample was transferred to a 250 ml conical flask kept in water bath for alkali treatment. 75 ml of 17.5% caustic soda was measured using a measuring cylinder at 20°C. 15 ml of 17.5% NaOH was added and fibres were macerated gently with a flattened glass rod for 1 minute. 10 ml more NaOH was added and the solution was mixed for 45 seconds. 10 ml NaOH was again added and mixed for 15 seconds to make lump free slurry.
Eventually using the NaOH and the acid’s consumed moles, the equivalent mass will be determined. Procedure: Part 2: Obtain 45mL of NaOH, and then weigh 0.3-0.4g of the unknown acid (KH2PO4). Dissolve the acid into 20.00mL water.
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 SPM was set to 34oC. Seven test tubes were used in determining the optimal temperature – in the first test tube a solution of 5mM p-Nitrophenol Phosphate with a buffer of pH 8 was used, when the 10 units of enzyme AP was added into the test tube (final volume of 3ml) then the experiment was immediately under way. The test tubes contents were hastily transferred to the cuvette and the put into the SPM, the absorbency readings were recorded every minute for a total of 10 minutes. This haste ensured the enzyme would not have ample time to form product that would have been unaccounted for, thus resulting in skewed readings and a faulty report. When the results for the first test tube were recorded, then the next solution/mixture was prepared. The second test tube was exactly the same as the first, the only difference being that the SPM was this time set to 35oC.
However, any doubts regarding the results may be traced to a few elements of the experiment that lend themselves to possible error. The following factors may have contributed to potential errors in the experiment; the need to zero the machine between each of the readings in obtaining the absorption spectrum and the resulting peak wavelength, the precision with which a person can accurately adjust the needle on the spectrophotometer to zero is limited, not putting in the inaccurate amount of cobalt chloride or water into the substance, and getting oil from our fingers onto the
Record your data and then flush. Step 7. Replace 20 MWCO membrane with 50 MWCO membrane Step 8. Repeat steps 3-5 and collect your data.
Using the thermometer, the temperature was measured and recorded. Then, the 25-mL graduated cylinder was filled with 25 mL of distilled water, and its mass was measured and recorded. The density of the water was found using the temperature and the Density of water index. Moreover, the calculated volume of water was calculated using the formula of density, and the difference between observed volume and calculated volume was found. This process was then repeated using the 50-mL beaker and the results were recorded.
At 10-minute intervals, we would take them out and weigh them again for 30 minutes. We repeated this experiment using another five set of cups that contained 50 mL of 1M sodium chloride. After gathering the data, we calculated the change in weight of the yam cores, performed a t test and constructed graphs. After performing a t test, I found the p value
Before starting the heating process, measure the weight of the crucible with its cover first and then tare the balance, and after that adding about 1 gram of the sample to the crucible with its cover, and then weigh it. Moreover, it is possible liberating harmful gases during the process of heating; therefore, being careful is important. The heating process ends when this sample changes the color to brown because water of hydration is removed to the sample. Additionally, give time to the small cool down and measure its weight. Next, transfer the sample to a 50 mL beaker and mixes with distilled water, which gets by rinsing the crucible with its cover in 8mL, so the solution is generated.
The purpose of this experiment was to create two 40 mL buffers and evaluate its buffer capacity at pH 4. To do this, buffer #1 consisted of the mixture of 0.5003 M acetic acid and .50 M sodium acetate, while buffer #2 consisted of the mixture .5003 M acetic acid and .4289 M NaOH. Within each mixture, there is a ratio of conjugate acid to conjugate base. By using the Henderson Hasselbalch equation, the volume for the base and acid to buffer the pH of solution at 4.0 were calculated.
The motivation of this investigation was to achieve 85% of methanol recovery from the distillate. II. Methodology: The distillation column was analyzed theoretically using McCabe Thiele to establish the number of stages required for separation. The vapor-liquid equilibrium (VLE) data for methanol and 2-propanol was used to plot curves of methanol-vapor fraction versus methanol-liquid fraction, and methanol liquid-vapor fraction versus temperature.