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Ethanol (4.0 mL) and benzoin (0.5004 g) were added to an 25 mL Erlenmeyer flask. The flask was first swirled at room temperature for the solutes to dissolve. Some heat was also added to facilitate the dissolving. Once completely dissolved, sodium borohydride (NaBH4) (0.102 g) was added with a microspatula over the course of several minutes. After, the mixture was swirled for 20 minutes at room temperature. 5 mL of water and 0.3 mL of 6M hydrochloric acid were added to the flask after being cooled in an ice bath. 2.5 mL of water was then added to quench the solution. 1,2-diphenylethane-1,2 diol was collected with the vacuum filtration and rinsed with ice cold water.  The product was left to dry for 15 minutes on the filter. Once the product was weighed, the crude yield mass was determined of 0.512 g. The crude product was then recrystallized with 1.5 mL of acetone. Once the crystals were dry, the melting point of the purified 1,2-diphenylethane-1,2 diol was measured to be 137 degrees celsius and the percent yield and mass yield were.

Karyotyping is a representation of chromosomes captured at metaphase. When the chromosomes reach the metaphase phase, the division is halted and then the chromosomes are arranged by size into a karyotype. There are several different kinds of banding including, G-banding, Q-banding, C-banding, and R-banding. G-banding dyes heterochromatin in the chromosomes, Q-banding finds areas rich in A-T vs. G-T and dyes them to identify the homologous chromosomes. C-banding dyes centromeric heterochromatin and R-banding is the reverse of G-banding . Today, softwares can analyze the banding types once it is dyed and arrange them. Moreover, DNA in the nucleus are found in two forms, heterochromatin and euchromatin. Heterochromatin is tightly packed DNA material, whereas euchromatin is loosely packed chromosomes that become active during transcription.

The modern gene editing tools have the potential to treat diseases with a unique approach. With the use of CRISPR-Cas9 protein complex, specific genes are targeted and the DNA sequence is then modified. Researchers are currently practicing with gene editing in various subjects and performing the techniques in experimental research. On the other hand, scientists are delaying the use of gene editing for safety concerns and increased regulations. For our project, we will be discussing the controversial ethics of gene editing and managing more focused topics about the various applications of gene editing. In addition, surveys will be conducted for each topic to collect the opinions of students at UMass Amherst.

Clostridium difficile is the inflammation of the colon caused by the clostridium difficile bacteria. The symptoms occur when there is a lack of healthy bacteria in the body. Symptoms often include diarrhea, stomach pain, and fever. The common method for treatment, as with most bacterial infections, is to use antibiotics; however, even with antibiotics, the risk remains for the infection to come back. In recent years, researchers and scientists have consulted a different treatment approach with fecal transplant. The fecal matter from a healthy person can potentially restore the healthy bacteria in the infected colon of a patient with C.diff, or Clostridium difficile. It is an effective combination of antibiotics destroying bacteria, both healthy and infectious, and the fecal matter restoring only the healthy bacteria to reduce the risk of the disease resurfacing. So far, this process has been shown to be successful, however, critics are concerned about the pricing for patients. Additionally, while not necessarily a concern, rather an unknown, the methods are still under review by the FDA. This breakthrough has helped patients feel better within hours after a single treatment, and can be administered via colonoscopy or capsules containing fecal matter.

On the synthesized cyclohexene, gas chromatography was performed. At least one compound was present because there was one peak observed. The gas chromatography had a retention time of 0.386 seconds and the large peak was recorded at 0.386 seconds. The area of the peak is 10,530 and has 100% of the area, suggesting that the cyclohexene was very pure.

Infrared spectroscopy was also performed on the same cyclohexene end product. The peak for the alkene group was seen at about 2,800 1/cm. The graph for this compound has a major peak at about 2840-3000 1/cm, suggesting that the cyclohexene contains both alkenes and alkanes and that the experiment was successfully performed. Moreover, the frequencies of the infrared can determine the bonds as different interatomic bonds do not all vibrate the same. More specifically, double bonds have higher stretching frequencies than single bonds.

In this experiment, cyclohexene was synthesized via the dehydration of cyclohexanol using 85% phosphoric acid. First, 0.5 mol phosphoric acid and 2.003 g of cyclohexanol formed a mixture and proceeded through fractional distillation. The experimental boiling point was measured to be 68.5℃.

    Two functional tests were used to determine which functional groups were present. In the first test, bromine in dichloromethane was added to cyclohexene product in a vial and into another separate vial containing cyclohexane. The vial containing the cyclohexene observed no change in color, which concludes that the compound contained an alkene because the reaction between bromine and alkene formed colorless dibromide. On the other hand, alkanes react slower with bromine by free radical mechanism initiated by light, which explains the color change of red-brownish. In the second test with 1% potassium permanganate and 10% sulfuric acid, the vial containing cyclohexene had no color change, however a brown precipitate was observed after all the drops were administered. The precipitate formed was manganese dioxide, which forms between reactions of potassium permanganate and alkenes. Lastly, the vial with cyclohexane turned purple because the potassium permanganate did not react with alkanes.

To a tared flask, 2.003 g of cyclohexanol and 0.5 mL of 85% phosphoric acid were added with boiling chips. A fractional distillation column was setup to purify the cyclohexene. The purified sample was then extracted and placed in a reaction tube with 1.0 mL of distilled water. A bottom layer formed, it was thoroughly mixed and then left still to settle. The bottom distilled water layer was removed with a pipette and placed in a bin marked as waste. The sample was extracted with 1.0 mL of sodium hydroxide in reaction tube and thoroughly mixed. The lower layer was removed with a pipette and placed into the waste bin. The same procedure was repeated with 1.5 mL of saturated aqueous sodium chloride. The organic phase was then transferred to a clean vial. For the dehydration, calcium chloride spheres were added and left to dehydrate for five minutes. Once completed, the organic layer was pipetted into a clean vial that did not contain calcium chloride. Gas chromatography analysis  was then performed to determine the purity of cyclohexene. Infrared analysis was then used to determine which functional groups were present. The end product was used in two chemical tests to determine the functional groups present. In the first test, 4 drops of 3% dilute bromine solution in dichloromethane was added dropwise to the cyclohexene product, about 0.25 mL, where no color change was observed. However, in cyclohexane, about 0.25 mL, a red-brownish color was observed. In the second test, 2 drops of 1% potassium permanganate and 10% sulfuric acid was added to cyclohexene product, about 0.25 mL, where no color change was observed but there was a brown precipitate. 1% potassium permanganate and 10% sulfuric acid was added to cyclohexane product, about 0.25 mL, and a purple color was observed.

Clostridium difficile is the inflammation of the colon caused by the clostridium difficile bacteria. It results from a lack of healthy bacteria in the body that causes diarrhea, stomach pain, and fever. The common way to treat this disease, likewise for several other bacterial infections, is with antibiotics, however a risk remains for the infection to come back. In recent years, researchers and scientists have consulted a different treatment approach with fecal transplant. The fecal matter from a healthy person can potentially restore the healthy bacteria in the infected colon of an affected patient and restore the bacteria killed off by the antibiotics. So far, this process has been shown to be successful, however critics are concerned about the pricing for patients and the methods are still being reviewed by the FDA. This breakthrough has helped patients feel better within hours after a single treatment. The fecal transplant can be admitted through colonoscopy or capsules contained fecal matter.

Fractional distillation is a more viable technique than straightforward distillation because fewer material is lost throughout the procedure. Therefore, the distilled compounds are more purified in the results. The copper wire in the fractionating column acts to copy multiple distillations in one round of fractional distillation.

During fractional distillation of unknown 20, I observed a higher boiling compound at about 79 degrees celsius and a lower boiling compound at about 56 degrees celsius. There was a 1:1 ratio of higher and lower boiling points from the product collected in the vials. It can be determined that the lower boiling point compound is acetone because acetone boiling point is 56 degrees celsius. Moreover, the identification of the higher boiling point compound is 2-methyl-2-propanol. The theoretical boiling point for 2-methyl-2-propanol is 82 degrees celsius, which is about 3 degrees different from the experimental boiling point. The difference could be due to human error by heating the compound too quickly. The experimental results for this procedure are accurate because fractional distillation provide pure compounds that are less likely to be lost during the process.

In the experiment of TLC, unknown 3 moved 2.1 cm. After conducting the experiment, the retention factors were calculated using Rf=y/x, ‘y’ was the distance the spot traveled and ‘x’ was the distance the solvent traveled. The average for each compound’s Rf was calculated. Aspirin’s Rf was 0.2115, Acetaminophen Rf was 0.358, caffeine's Rf was 0.089, unknown 1 Rf were 0.426, 0.089, and 0.375 and unknown 3 Rf was 0.360. Based on the Rfs and spotting, unknown 1 contains acetaminophen and caffeine. Unknown 3 contains acetaminophen but no caffeine. As a result, unknown 1 is not pure because it contains multiple compounds although unknown 3 is pure. Potential errors could be caused by human error if the solvent did not rise high enough.