Electrophilic Aromatic Substitution Reaction Lab Report

1) Percentage yield experiment: First we measured 20cm3 of sulphuric acid into a beaker using a measuring cylinder, this will help us determine the percentage yield at the end of the experiment. We then heated the beaker containing the sulphuric acid using a Bunsen burner in order to heat it up for the copper oxide to mix with. We then weighed out 1.02g of copper oxide and added it to the acid and stirred it whilst doing so, we did that until the liquid turned blue, this proves that the chemicals have mixed together. We then weighed this liquid which will help us determine the percentage yield. We then filtered the liquid off which gave us the amount we obtained.

After the 30 minutes is done, the tests tubes are then immersed in a 100 degrees Celsius methanol water bath for 15 minutes. Once the samples become frozen, put in a lyophilizer at a temperature of -109 degrees Celsius. The samples are allowed to completely dry. After 6 hours remove from the lyophilizer. Acetonitrile at a PH of 7 (neutral) is added to each of the test tube samples.

21) A sixty-minute timer was started to see how the 18 Na⁺Cl⁻ (mM) solvent diffuses through the 50 (MWCO) Dialysis Membrane. 22) The conclusion was jotted down. 23) The 50 (MWCO) Dialysis Membrane was removed from between the beakers and put back into the original membrane container. 24) Both beakers are emptied and cleaned to begin the next test. 25) The 100 (MWCO) Dialysis Membrane was placed in the middle of the left and the right beaker.

It was then washed off with ether after the drying process was finished and allowed 5-10 minutes for the drying of the ether solution. ?M HCl was added drop wise to tube 2 to neutralization, while testing the solution with litmus paper. A boiling stick was then added to the tube and heated cautiously to bring most of the solid carboxylic acid into solution. The tube was then allowed to cool slowly to room temperature then cooled in ice. The solvent was removed and the residue recrystallized from boiling water.

The test jar was places in the ice box containing freezing mixture. In the determination of the cloud point the sample was cooled and inspected at intervals of 2°C until a cloud and haze appeared, than noted the thermometer reading. This was the cloud point. As soon as cloud point was determined the test jar was further cooled and inspected at intervals of 5F. Until it ceases to flow when test jar was tilled & kept horizontal for 5 seconds.

Dissolve the salt in 120 ml of tap water. Add 60 ml 6 M Hcl and stir the mixture with a glass rod. Add 24 g solid Nacl to the solution and stir the mixture for about 2 minutes. Support a 500 ml separatory funnel on a ring, close stopcock and then a clean beaker is placed beneath the exit tube. Transfer the aqueous solution from the beaker to the separatory funnel.

Once a prevalent color change had been observed at approximately 4 minutes (blue green color) the crucible was set on the counter using the tongs to cool for approximately 5 minutes. The appearance after this period resulted in another color change back to white. The crucible, lid, and hydrated copper sulfate was weighed again to calculate the mass of water lost by dehydration (described in table 1.3). This was done by subtracting the final mass by the initial mass of the crucible, lid, and compound. The mass of the crucible would remain unchanged while the mass of the compound would be altered.

The drop rate was adjusted to 1 to 2 drops/second. 10.0 mL of the NaOH solution was allowed to drip away into a waste beaker. The exact volume of the sodium hydroxide solution used was determined. A clean 250-mL beaker was taken and around 0.3 to 0.5 g of potassium acid phthalate was weighed into it. 50 mL of distilled water was approximately added to this 250 mL beaker and gently swirled so that the solid (potassium acid phthalate) got fully dissolved into the water.

This diluted solution will be used in the assay as duplicate samples. Then, 1.0mL of standard glycine solution containing (7.5mg/mL) was diluted to 100mL with water using a volumetric flask. This solution contains 1.0µmole/mL of glycine. 8 tubes were set up according to the following protocol and 2.0mL of ninhydrin reagent was then added to each of the 8 tubes and were placed in a boiling water bath for 20 minutes. After 20 minutes, the tubes from the bath was carefully removed, cooled in a beaker of cold water, then 8.0mL of 50% ethanol was added and mixed well.

The crude product contained acetanilide, and acetic acid, which was the impurity. Recrystallization, which was used to purify the contaminated acetanilide, required a suitable hot solvent which dissolved all the crude product, but upon being cooled, since

4. The solutions were allowed to cool to room temperature using an ice bath. 5. 150 ml of the solution in beaker A was added to the separating funnel with 10ml of chloroform. The funnel was gently shaken and vented to release the pressure.

The goal of this experiment was to synthesize the unknown ester through Fischer Esterification. This procedure involves treating a carboxylic acid with an alcohol and a strong acid catalyst. This procedure was also catalyzed with heat at 160oC-180oC, to keep the temperature from exceeding the boiling points of the compounds in use. The acid catalyst protonated the double bonded oxygen atom to force the atom to pull two electrons away from the double bond in order to stabilize the atom’s charge. As this electron shift occurred, the alcohol attacked the carbocation that lost its double bond.

Two chemical reactions are carried by adding sodium hydroxide to the acidic solution from Part I. During the first reaction is the neutralization of the excess of nitric acid in the mixture by sodium hydroxide. The second reaction takes the place after naturalization is a complete and NaOH is in excess. While the liquid inside the beaker is being stirred, with the stirring rod, 10 ml of 6 M NaOH is poured into the solution from Part I at 1 mL at a time. After each 1 mL the solution is tested for acidity with red litmus paper.