After adding the acetic acid and hydrobromic acid to the solution, and heating and recrystallizing the solution, the product triphenylmethyl bromide was created and had a mass of 0.103 g. The theoretical yield was calculated by determining the limiting reagent in the reaction. The triphenylmethanol was the limiting reagent in the reaction. The total amount of mass from the triphenylmethanol was converted to moles by using the molar mass of the triphenylmethanol. The amount of moles was then converted into grams to determine the theoretical yield, 0.125 g. The percent yield was then calculated by dividing the actual yield by the theoretical yield and multiplying the result by 100%. The percent yield was 82.4%.
As seen in table 1, the theoretical yield was .712 g of C_17 H_19 NO_3. The % yield of this experiment was 7.51 % of C_17 H_19 NO_3. . This low yield can be explained from a poor recrystallization technique combined with potential contamination. Throughout the experiment, the mixture changed color from green, orange, to yellowish lime, and eventually clear.
The % yield was greater than 100% because the actual yield was greater than the theoretical yield. One error that may have caused this result to occur was that the copper may have not completely dried over the time it was left. If water was still inside the copper, it would increase the mass of the actual yield. If the copper was left in the beaker to dry for a longer time, it would help decrease the mass of the copper (as the water would be completely dried out) and bring the actual yield down.
(150.22g/mol)(3.5 x 10^-3 mol of nucleophile) = 0.525 g Actual yield = 0.441 g, Percent Yield = (0.441g/0.525g) x 100% = 84% 10. Percent recovery from recrystallization = (0.172g/0.441g) x 100% = 38% 11.
3. In this experiment, the percent yield was 90%. This number implies that there was little error in this experiment. However, this result could have been caused by certain external factors.
The percent recovery of the copper was calculated using the equation, percent recovery = (the mass of the copper recovered after all the chemical reactions/the initial mass of the copper) x 100. The amount of copper that was recovered was 0.32 grams and the initial mass of the copper was 0.46 grams. Using the equation, (0.32 grams/0.46 grams) x 100 equaled 69.56%. The amount of copper recovered was slightly over two-thirds of the initial amount.
After this 2 week experiment, a lot of data has been collected. As hypothesized in the beginning, the seeds treated with acid rain did not grow as much as those treated with regular water. At the beginning of the each Test, the seeds were all very small and hard. The pea seeds measured 1/4 of an inch, the corn seeds were also 1/4 of an inch, and the bean seedlings were 1/2 of an inch in length. In appendix A and B, the picture shows what the seedlings of both tests look like without any watering.
The needed mass for reactant A was 3.52 grams and the needed mass for reactant B was 2.12 grams. The moles of product C (CaCO3) were also required to have been calculated using mass- to- mole conversion, but the mass was already established, so its mass was not calculated. Results Calculations used to determine the percent error 2.3 g CaCO3 - 2.00 g CaCO3 2.00 g CaCO3 x 100 = 15 % Reactants A and B’s masses were not similar, but the numbers were also not drastically different. Obviously, product C’s solution is different because moles were calculated as opposed to a mass.
The final product weight for percent yield was only the solid E product, which missed one half of the final product produce. If both products were weight, the percent yield would have been larger that it was. Instead of 22.33%, it could have been 44.66%. To prove that both products were obtained, but only one of the two products was analyze, a TLC plate of the DCM layer, that contains both products, and of the final product, was obtain.
The actual data is the result on our experiment vs theoretical, which is based on the calculations above. I have also learned to pay more attention to draining out all of the product completely before continuing to test the experiment, as any small drop of contaminant can veer our results into a different
Energy Lab Assignment: Photosynthesis Abstract The purpose of this experiment was to determine whether film on white light had an impact on the transmittance percentage and to establish whether the film's color was relevant to the outcomes. In this experiment, the photosynthetic absorbance of spinach thylakoids was measured using a spectrophotometer. The hypothesis was that white light would have the highest transmittance percentage compared to green film on white light and red film on white light.
Exponential Growth of E. coli Escherichia coli, also more commonly known by the name E.coli, is a commonly found in the large intestines of warm-blooded organisms. The strains of bacteria that are found in the body are not harmful and can actually aid the body in things like digestion. E.coli, like a lot of bacteria, have a growth stage that can be expressed exponentially in both an equation and on a graph. In order to calculate and predict the number of E. coli bacteria cells growing on a plate of medium after a certain amount of time, an equation for continuous exponential growth can be created using the formula A=Pe^rt, in which A represents the ending amount of bacteria, P represents the number of bacterial cells initially on the plate,
In theory, it had a maximum yield of 100 megatons if it were to have included
For example, in the response experiment, a yeast solution was prepared without sugar mistakenly and thus had to be prepared again. This suggests that other errors in preparation and measurement could have been encountered. For the future, careful measurements using clean uncontaminated flasks would eliminate possibilities of such error. A source of error for the metabolism experiment involves the yeast’s yellow hue. It is possible that the color of the yeast caused the solution to look more
Hypothesis: Increasing substrate concentration will increase the initial reaction rate until it stops increasing and flattens out. Independent Variable: Substrate concentration Dependent Variable: The substrate itself, 1.0% Hydrogen Peroxide How Dependent Variable will be Measured: Hydrogen Peroxide will be used in every experiment, just with different test tubes. The amount of Hydrogen Peroxide in the mixing table is the amount that will be added to each test tube.
