As mentioned in number 13, the data for the melting point makes sense because my pure product and given compound almost perfectly matched. 17. Again as explained in number 14, the TLC data made sense because my pure compound and 4-tert-butylbenzyl phenol had similar distances from the solvent origin of the plate. The presence of benzyl bromide and benzyl alcohol also explains how not all the product dissolved in the filtrate. The possible explanations and changes to make are similar to the previous questions.
Since the solvent is nonpolar, we would expect carotene to have the lowest Rf, then xanthophylls, and chlorophylls would have the highest. As discussed before, this is because chlorophylls are the most polar of the three and carotenes are the least polar of the three. Based on my results, I would say that the packing and running of the column was effective in separating the pigments as there were quite different Rf values for the original than for the other two colors and the band for the yellow was nothing like the bands for the green. There were no limitations in procedure which negatively affected the end results, so there is nothing I would change to it going
In this experiment, 293 mg of aldehyde was weighted for method 1 instead of 250 mg and. Although .7906 mg of phosphonium salt was added, this probably was not enough to complete the reaction. The only significant change throughout method was 1 was that the yellowish mixture became slightly lighter. However, it was found that after vacuum filtration, there was some white and yellow
The product yielded a positive result, indicating the presence of an alcohol functional group. Brady’s test was also run and the product yielded a negative result, indicating there was no ketone present. These tests together indicate that the starting material fully reacted to form the product because the starting material had a ketone and the product did not have the ketone but rather had an alcohol. The gas chromatogram of the product was analyzed and had two peaks, the first at retention time 26.2 min and A of 125.33, with a concentration of 120.69, the second at retention time 27.2 min and A of 496.33, with a concentration of
This aqueous solution was then heated until all the dichloromethane evaporated off. An error could have occurred at this point in the experiment if the hot plate was too hot. If the hot plate was set above the boiling point of the ketone, the ketone could have evaporated of along with the dichloromethane. This would result in a lower percent yield of the ketone. To prevent this from happening, the hot plate should not exceed 130˚C, so no matter what ketone was isolated, it would not evaporated off.
It was found that the compound was solid and white in color. The unknown compound was then tested solubility in water and the compound was soluble in the water. The flame test was performed for four know compound calcium chorine, sodium chlorine and ammonium chorine and the unknown compound. When unknown compound was put on the fire different color are produce. When we smell the unknown compound it indicated the presence of chorine.
Based on the references take, a mixture of extra virgin and light olive oils would most likely have features resembling regular olive oil. It would have a lighter but still bright yellow color, and a wavelength and absorbancy between the ranges for extra virgin and light olive oil. Without the use of a spectrometer, the concentration of an unknown solution of nickel (II) nitrate could be estimated based on the coloring. The more concentrated the solution the darker green in appears and, vise versa, the less concentrated the lighter the solution will become as it is diluted by water. You could use Beer’s Law to calculate the unknown concentration of cobalt (II) nitrate as Beer’s Law states that a solutions concentration is proportional to the solutions concentration.
This could have been because it was more sterically hinder since the carbonyl group was connected to a primary carbon. The third ester which reacted was ethyl butanoate since it was a bit more sterically hinder than the ethyl acetate because the carbonyl group was connected to a secondary carbon. Both ethyl acetate and ethyl butanoate had electronic factors of being electron donating making the carbonyls less reactive so the order depended more on the steric factor. The slowest ester to react was the ethyl benzoate because of the greater steric hindrance since the carbonyl was connected to a benzene ring which making it hard for the nucleophile to attack. The carbonyl was directly connected to a tertiary carbon, but that was also in a ring.
A solution to this error would have been to use more precise scales like scales that measure to 3 decimal places rather than to 1 decimal place to get a more exact value instead of a less accurate measurement. A final source of error that was made during the experiment is the concentration of the products used were low so there might have been other thing in the vinegar to add mass to the final solution. A solution to this error could have been to use a more concentrated acetic acid because the vinegar could have other products that could ruin your calculations in the end if it did not dissolve with the
For example, dopamine has a Km of 95 and a Vmax of 11 x 105. Both of these values are fairly high and would not make an effective substrate for catechol oxidase since the enzyme has a low affinity for the substrate. An example of a good alternative substrate would be 4-methylcatechol that has a low Km of 1.1 and a Vmax of 3.4 x 105. The enzyme now has a high affinity for the substrate and therefore requires less substrate to meet its Vmax. The substrate for the sweet potato catechol oxidase is N-phenylthiourea.