Before the start of this experiment, the theoretical yield was calculated. Based off the data, it was found that the limiting reagent is 3-nitrobenzaldehyde. The theoretical yield is determined by relating the moles of the limiting reagent to the moles of the anticipated product by a ratio obtained from the overall equation. The theoretical yield was calculated to be 1.3 g. However, the actual yield obtained was greater than the theoretical yield; in other words, the actual mass of the product was higher than the theoretical mass. This led to an abnormally high yield of 320% and an impure product. Though the experiment was carried out smoothly, errors may have occurred that led to an actual mass of 4.166 g for the crude chalcone. After the …show more content…
Data Table 2 shows the results gathered after the purification of 3-nitrochalcone. Since only half of the crude product was used, the theoretical yield for the crystallized product was determined to be 2.1 g. This led to a percent yield of 39%. The melting point of the crystallized product was also determined to be 142℃, which differed slightly from the literature value of 146℃. As a result, the product, 3-nitrochalcone, was not completely pure. It probably contained water and alcohol, because any impurities would have lowered the melting point. Considering the fact that the crude product was not thoroughly dried before purification, water and ethanol were already in the product. Even after crystallization into “pure 3-nitrochalcone”, the product was also not completely dried. The yield should have been much lower than 39%. If the product is not allowed time to dry, not only water, but methanol, which was the solvent that was used to crystallize the crude, would be in the product. Both the crude and crystallized 3-nitrochalcone were analyzed by infrared spectroscopy to test and prove these …show more content…
The two peaks next to each other, 2360.23 cm-1 and 2341.78 cm-1, most likely indicated a nitrile or alkyl stretch. These peaks disappeared in the spectrum for the crystallized 3-nitrochalcone, though. The peaks were most likely as the result of an incomplete reaction or a reaction that did not go to completion. The product probably did not completely tautomerize, showing an alkyl or nitrile group. The crude product was also not completely dried, as indicated from the presence of an -OH group at the 3383.38 cm-1 peak. Figure 2 depicts the infrared spectrum of the crystallized product. The two peaks, signifying the nitrile or alkyl stretch, were still on the spectrum, but smaller. However, a peak at 3380.36 cm-1 indicates that an OH stretch is still present in the crystallized product. This verifies that the product was not pure; that –OH group was likely from methanol, the solvent used to purify the crude product. In order to remove the methanol/OH group, the crystallized product was left to dry in an oven for several minutes to spur dehydration. After that, another IR spectrum was taken for the dried product (Figure 3). In this spectrum, there was no alcohol peak, which indicates that the product became pure; the compound lost the hydroxyl group and no methanol was found in the pure product. As a result, Figure 3 is the desired
An Erlenmeyer flask was used to accommodate the largest volume of recrystallization solvent calculated and was cooled in an ice bath to increase the yield of crystals. The solid was collected by vacuum filtration and washed with a small amount of ice water. The product is then dried to a constant mass by use of an oven and weighed. A small amount of the unknown was compared to two samples of acetanilide and phenacetin for a melting point range to determine the identity. The temperature of the unknown was recorded when the first trace of liquid can be seen and when the unknown was completely liquid.
The goal of this lab was to expand and centralize our infrastructure by adding a Windows Server 2012 VM and configuring it with a number of key services. Some of the services that we deployed on the Windows 2012 VM had previously been configured on other machines, namely the RHEL VM from Lab 2. We began by installing and configuring the server itself, ensuring that we provided it with ample memory and processing power. Next, we configured DHCP, disabling the DHCP service running on our RHEL VM. We then continued by installing Active Directory and DNS on the Windows 2012 VM, disabling the DNS server running on the RHEL VM in the process. The DNS server on RHEL would later be reactivated as a secondary (slave) server. We then proceeded to set up monitoring for both DHCP and DNS. This monitoring was configured locally on the Windows 2012 VM using the Performance Monitoring utility, and also remotely via OpsView. Finally, we installed Microsoft Baseline Security Analyzer on the Windows VM. This was the first lab where it felt like we
1. Our percent yield for alcohol was 84.2% which is average. We rushed through our vacuum filtration and probably did not let the solid dry long enough and might have not transferred all of the solid to the vacuum filtration from the beaker.
Experiment 55 consists of devising a separation and purification scheme for a three component mixture. The overall objective is to isolate in pure form two of the three compounds. This was done using extraction, solubility, crystallization and vacuum filtration. The experiment was carried out two times, both of which were successful.
Therefore, the experimental yield is larger than theoretical yield. This indicates an error in how the result was produced, this could have been caused by a number of different factors. The first possible reason for this error could be a result of the drying process of the amino group. The product was left out for several minutes, however despite this the product was still wet after the drying process over should have been complete, thus increasing the mass of our product and therefor increasing the percent yield. Another possible factor in this over calculation is an excess of 4-aminophenol, which was 1.008g instead of 1 gram. Additionally, a number of errors could have been the result of time management, which in the future will need to improve. In the process of cooling reactants (4-aminophenol and acetic acid) in ice water, time could have been used more effectively in other parts of the experiment. This could have been a major factor in why 3 hours were used to complete the lab. Despite these potential errors we found that both acetaminophen and 4-aminophenol were alcohols as they produced a color change in the Cerium Test. This means that both these compounds have a hydroxyl group which coincides with the resulting chemical structure record on our green sheet. Using the Universal Indicator Test the pH of 4-aminophenol was found to be slightly basic whereas the acetaminophen was acidic. These
The product was then suspended in 2 ml of water with a stir rod in a 50 ml Erlenmeyer flask and heated to boiling. Water was added in one milliliter increments until all the product was dissolved (18 ml added total). The saturated solution was allowed to slowly cool, and gradual white crystal formation was observed. Recrystallized product was collected once more by suction filtration with the Hirsch funnel once crystallization ceased. Collected product dried on a watch glass for a week, weighed 0.14 g (1.2 mmol), and the melting point was 139°-141°
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Numerous factors can determine the percentage yield of a chemical reaction. Such as the nature of the reaction, the conditions in which the reaction is carried out and the nature of the reactants used in the reaction. In this investigation the percentage yield was to be determined using the following chemical reaction:
In this lab we will be studying electric field plotting through the use of various apparatus. The equipment we will be using includes a digital voltmeter, voltage probes, carbonized acetate sheets, battery, and other tools of measurement. The goal of the lab is for us is to be able to plot lines for charge distributions and to create electric field lines by providing an electric current through carbonized sheets. Once we have completed constructing the electric field lines for the plate charge distribution, we will continue to calculate for the electric field (E = Vx) and begin to plot for the dipole charge distribution. When we have collected all the data needed, we then will finish calculating for all the remaining variables and complete the rest of the lab report.
The Lithium Nickel Manganese oxide battery is still in its experimental stages. It consists of a 25% nickel substituted in a LiMn2O4 spinel. This is because Manganese will have 4 electrons in its valence shell which will avoid the Jahn-Teller distortion caused due to the Mn3+. Due to the oxidation or reduction of Nickel ions which leads to the transfer of electrons which corresponds to electric current. LiNi0.5Mn1.5O4 takes shape in two conceivable crystallographic structures concurring the cationic sub lattice: the face-focused spinel (S.G. Fd3m) named as "cluttered spinel" furthermore, the straightforward cubic stage (S.G. P4332) named as "requested spinel". This addition allows
In this section we first briefly explain the properties of a first-order Delta Sigma modulated bit-stream. Based on these properties, we propose the P-N pair method to process the Delta Sigma modulated bit-streams.
Based on prior calculations, expected yield for the alkene products was 79.5%. The actual yield was not as high, resulting in a 28.4% yield. Even with this relatively small yield, the reaction still went to completion as indicated by the GC results in Figure 2. This is known because there is no presence of 2-methyl-1-butanol within the GC spectra. Only the two desired alkene products with
The reaction took place in a conical vial and .2mL of each of the reactant samples were added to it along with some 95% ethanol. Two drops of NaOH were added shortly after and stirred at room temperature for fifteen minutes. The vial was cooled in and ice bath and crystallized. Vacuum filtration was performed to filter the crude product. The crude product was recrystallized using methanol and filtered again. We made one change to the procedure and instead of using .7mL of ethanol we
The week after, a recrystallization was performed on the previous week’s crude product. The product ethereal solution was first heated on a steam bath until dry. During the heating, a beaker of methanol was collected and also placed on the steam bath. Once the product was dry, it was cooled to room temperature and then placed in an ice-water bath. The now boiling methanol was added to the crude crystals and a recrystallization was performed. Once completed, the now purified product was collected via Buchner vacuum filtration and stored in drawer to dry for a week. Afterwards, a melting point range of the purified product was obtained by using a Mel-temp apparatus. Lastly, an
The first portion of the lab was about preparing the standard curve for the reaction products. In this part we already know the concentration of the product, Nitrophenol. So, to perform this we took six test-tubes and filled each with 1ml of standard labeled with S1-S6 respectively. For example 1st =S1, 2nd=S2, 3rd =S3 and so on. After that we measured the absorbance of each test tubes setting the first one as blank. And the data is recorded in the table (5.1). After recording the reading we constructed a Nitrophenol Standard curve by plotting A410 on y-axis and concentration on the x-axis as on figure (5.2). The second portion require us to prepare acid phosphatase from the wheat germ extract. But, this part of the lab was already