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During distillation, the temperature at which the first drop was recorded was at 66^oC and plateaued at 70^oC. Although cyclohexene has a boiling point of 83^oC, the decrease in the boiling point could have been to the impurities of the mixture, which was later washed out. Although human error in the placement if the thermometer could have been the reason of the lower temperature recorded. The initial mass was 2.013g with a final mass after distillation was 0.722 g. The percent yield was 35.9%, which was caused by the removal of the alcohol into water. The water was then removed from the cyclohexene via washing. 

In this lab, cyclohexanol was distilled with a phosphoric acid catalyst, giving a 35.9 % yield of cyclohexene. After the GC, the product I produced was in fact cyclohexene. The standard GC graph shows a retention time at 0.205. The GC graph obtained from the cyclohexene product showed a retention time of 0.175, which is not much difference than the standard. The IR analysis showed the results have a major dip between 3200 and 2800 l/cm. The standard IR analysis shows a dip from 3061.03 to 2837.29 l/cm. The results obtained are a clear indicator that the product was cyclohexene. There is a dip at 1635.00 l/cm indicates that there is a double bond in the product. Since there is no presence of a dip between 3400 to 3200, there is no alcohol present in the product. After these two methods of analysis, the results can confirm that the product was indeed cyclohexene.

After the synthesis of cyclohexene, a work-up was done. In a small test tube, add 0.5 mL of cyclohexane. In another small test tube add 0.5 mL of the cyclohexene product produced. Three drops of 3% bromine solution in dichloromethane are added to each test tube, and note any color change. Then in a small test tube add 0.3 mL of cyclohexane, and in another small test tube add 0.3 mL of the cyclohexene product. Then add 1% potassium permanganate and 10% sulfuric acid solution to each test tube. Record any color change and manganese dioxide precipitate formation. Finally, perform a GC/IR analysis of the cyclohexene product.

In the fume hood, turn on the sand bath onto 40. In a small 10 ml round-bottomed flask add about 2 grams of cycloexanol (2.013 g used). Then add to the same flask 85% phosphoric acid (0.5 mL) and boiling chips. Using the distillation setup, distill the reagents into a collection vial at the rate of 20 to 30 seconds per drop. At the first drop write down the temperature ( 66^oC), and stop distillation when there is only 10% of liquid left in the flask. In the collection vial there will be two layers (water and cyclohexene). Using a pipet, the contents of the collection vial are transferred into a test tube. Then add about 1 ml of distilled water into the test tube. After remove the lower aqueous layer via pipet. After, add 1 mL of 1 M sodium hydroxide (NaOH), and again remove the lower aqueous layer. Add 1-2 ml of saturated aqueous sodium chloride, brine, to the test tube. For the third time remove the lower aqueous layer. The organic layer is left in the test tube, transfer the layer into a new vial. After, add CaCl₂ to the new vial until the CaCl₂ does not clump together. The vial should be capped and left to dry for at least five minutes. After the drying process, transfer the product into a new tared vial. The weight of the product was .722 g. Then calculate the percent yield, which was 35.9 %.

Distill cyclohexene and phosphoric acid, work up the collection vial, and analyze the dried product through infrared spectroscopy and gas chromatography. Do a chemical analysis to test for alkenes and then determine the percent yield. 

Exergonic and endergonic reactions share similarities and differences. The most known definitions of exergonic and endergonic reactions is exergonic refers to a reaction that gives off energy, while endergonic reactions take in energy. Although, there is more the energy. Both reactions require for an input of activation energy and use enzymes to lower the activation energy need to complete the reaction. Also the exergonic reactions have a negative value for the Gibb’s free energy value due to the reactants having greater free energy than the products. Endergonic reactions, however, are the opposite of exergonic reactions and have a positive Gibb’s free energy value because the products have more free energy than the reactants. Exergonic reactions are more favorable and spontaneous because of the negative value while endergonic reactions are less favorable and nonspontaneous.

In an allosteric enzyme reaction the shape of the graph is sigmoidal versus a hyperbolic like Michaelis-Menten enzyme. The sigmoidal shape is because the allosteric enzyme has two forms. The T form is when the allosteric enzyme is in its inactive form. The R form is when the allosteric enzyme is in its active form. The allosteric enzyme had multiple subunits in order to make the allosteric enzyme active the binding of a substrate to one subunit of the enzyme is required. Once the substrate binds to a subunit this causing for positive cooperativity to help bind more substrates to the other subunits. This cause the conformational change of all subunits from the T form into the active R form.

Exergonic reactions are similar and different than endergonic reactions. The basic definitions most people remember about exergonic and endergonic reactions is exergonic refers to a reaction that gives off energy, while endergonic reactions take in energy. Although, there is more the energy. Both reactions require for an input of activation energy and use enzymes to lower the activation energy need to complete the reaction. Also the exergonic reactions have a negative value for the Gibb’s free energy value due to the reactants having greater free energy than the products. Endergonic reactions, however, are the opposite of exergonic reactions and have a positive Gibb’s free energy value because the products have more free energy than the reactants. Exergonic reactions are more favorable and spontaneous because of the negative value while endergonic reactions are less favorable and nonspontaneous.

I took Statistics 240 during Fall 2016 in my sophomore year of college at University of Massachusetts, Amherst. I remember only a minimal amount of material from the course since I took it almost three semesters ago. I do remember the main topics such as standard deviation, standard error, variance, probability, and a few other her topics. As a biology major, I have encounters chi squared which is often used with experiments that have observed values and expected values. In Statistic 240, I learned about standard deviation and how if you square the value then you get variance. I also learned about probability and how probabilities can be added or multiplied in certain scenarios. Although there are things I remember, I would need to refer back to my old notes to remember fully how to use the equations and figure out certain problems.

The answer is Irreversible. This is known because the question says that once the acetyl group is added there is no enzyme to remove it. This means that one the product is created that reactant cannot be formed. Therefore only the irreversible enzyme would fit this description. A reversible enzyme would allow for the acetyl group to be removed.