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Lab report for characterization and classification of chemical reactions
Observing chemical reactions lab
Observations of chemical reactions lab
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This experiment synthesized luminol (5-Amino-2,3-dihydro-1,4-phthalazinedione) and used the product to observe how chemiluminescence would work. The starting material was 5-nitro-2,3-dihydrophthalazine-1,4-dione, which was, after addition of reaction agents, refluxed and vacuum filtered to retrieve luminol. Using two stock solutions, we missed our precipitated luminol with sodium hydroxide, potassium ferricyanide, and hydrogen peroxide, in their respective solutions, in a dark room, to observe the blue light
Fluorescence measurement provides very important information about the photochemistry of a particular molecule. The first part of this experiment was dealing with the fluorescence behavior of a Leucophor PAF. Information from both spectrophotometry and fluorimetry was used to measure the quantum yield as well as to explain why Leucophor PAF was use as commercial optical brightener. The second part of this experiment dealing with fluorescence quenching of quinine bisulphate solution (QBS) is the presence of sodium chloride.
Luminol can be synthesized by reaction 3-nitrophthalic acid with hydrazine to form 3-nitrophthalhydrazide. This compound is then reacted with sodium hydrosulfite to form luminol. To exhibit its chemiluminescence, luminol is reacted with an oxidizing agent which pushes electrons up to a higher energy excited state. When the electron drops back down to the lower energy ground state,
This week’s lab was the third and final step in a multi-step synthesis reaction. The starting material of this week was benzil and 1,3- diphenylacetone was added along with a strong base, KOH, to form the product tetraphenylcyclopentadienone. The product was confirmed to be tetraphenylcyclopentadienone based of the color of the product, the IR spectrum, and the mechanism of the reaction. The product of the reaction was a dark purple/black color, which corresponds to literature colors of tetraphenylcyclopentadienone. The tetraphenylcyclopentadienone product was a deep purple/black because of its absorption of all light wavelengths. The conjugated aromatic rings in the product create a delocalized pi electron system and the electrons are excited
Glow sticks get their “glow” when two chemicals are mixed together because of a chemical reaction. The chemical reaction is called Chemiluminescence. A Typical glow stick has a plastic tube with a smaller inner tube inside. There are three components, two chemicals and a fluorescent dye which accepts the energy and helps covert to light. There is more than one way to make a glow stick, but the most common uses a solution of hydrogen peroxide and phenyl oxalate ester along with the fluorescent dye. The hydrogen peroxide is in its own compartment away from the other two components until ready to use. The fluorescent dye is what determines the subsequent color of the glow stick when the chemical solutions are combined.
We thank the University of Oklahoma and the chemistry faculty for providing the space, instructions, and equipment for the development of this report and experiment.
From crime scenes to birthday parties to battlegrounds, chemiluminescence is a beautiful, yet useful phenomenon. The reaction of chemiluminescent molecules such as luminol can be used to detect bloodstains not visible to the naked eye or create long lasting, easily concealable light sources such as glow sticks. The goal of this experiment was to find the most appropriate solvent in which to dissolve luminol and examine the effects of adding reagents such as sodium hydroxide, bleach, and hydrogen peroxide to the solution, aiming to find the concentrations that caused the luminol to glow for the longest period of time. Although a rather complicated reaction, the luminol reacted best with a comparatively simple solution.
A bath was prepared using a 400 mL beaker filled halfway with water. The bath was then sat on a hot plate and lest to boil. 2g of salicylic acid was placed in a 125 mL Erlenmeyer flask with 3 mL of acetic anhydride, and 3 drops of concentrated sulfuric acid. The solutions were mixed and placed in the boiling water bath. The solution was left in the boiling bath for 30 minutes. The 125 mL Erlenmeyer flask was removed and placed on the side to cool to room temperature. Once cooled the solution was placed into a 150 mL Beaker that was filled with 20 mL of ice water. As the beaker was placed in the ice bath, it was simultaneously scraped with a glass rod until crystals formed at the bottom of the beaker. The crystal solution was poured into a Buchner
The goal of this experiment was to: create a dilute NaCl solution and calculate molarity, molality, and parts per million, experimentally determine the molarity of the same dilute NaCl solution through Mohr chloride precipitation technique, then, evaluate the accuracy by comparing the actual value to the experimental one. The actual molarity was calculated using the average density of three trials, mass of NaCl in solution, and molarity formula to be 0.0140 mol/L, the molality was calculated to be 0.0143, and the PPM was calculated to be 833. The experimental value for molarity, obtained through titration using AgNO3 as a titrant with Ag2CrO4 as an indicator, was averaged over three trials to be .01523 mol/L. Comparing experimental and actual values gave an estimated standard deviation of 0.00032 M with a confidence interval of +0.00079 at 95% and +0.0018 at 99%. The percent error for molarity was 8.8%. The experimentally determined molarity was functionally close to the actual molarity, however, some significant error in accuracy was observed. The amount of precision achieved with reasonable accuracy suggests this experiment could be used in testing salinity of separate bodies of water for comparison. The high % error inaccuracy, however, also suggests this should not be used in comparing minute changes in salinity in a single body of water.
The aim of this experiment is to carry out a reaction that results in the synthesis of Methyl Benzoate by Fischer Esterification. Methyl Benzoate is an organic compound, it is an Ester with the chemical formula C6H5COOCH3 and it is formed by the condensation of methanol and benzoic acid. Methyl Benzoate is strongly reminiscent of the fruit of the feijoa tree, and it is used in the making of perfumes. (6)
In our Biology Lab we did a laboratory experiment on fermentation, alcohol fermentation to be exact. Alcohol fermentation is a type of fermentation that produces the alcohol ethanol and CO2. In the experiment we estimated the rate of alcohol fermentation by measuring the rate of CO2 production. Both glycolysis and fermentation consist of a series of chemical reactions, each of which is catalyzed by a specific enzyme. Two of the tables substituted some of the solution glucose for two different types of solutions. They are as followed, Table #5 substituted glucose for sucrose and Table #6 substituted the glucose for pH4. The equation for alcohol fermentation consists of 6 Carbons 12 Hydrogens 6 Oxygen to produce 2 pyruvates plus 2 ATP then finally the final reaction will be 2 CO2 plus Ethanol. In the class our controlled numbers were at Table #1; their table had 15 mL Glucose, 10 mL RO water, and 10 mL of yeast which then they placed in an incubator at 37 degrees Celsius. We each then measured our own table’s fermentation flasks every 15 mins for an hour to compare to Table #1’s controlled numbers. At
The Calvin cycle occurs in the liquid of the chloroplasts of the plant, called the stroma.
The ingredients that will be included are: dish soap, 30% hydrogen peroxide, potassium iodide, and corn starch. Adding the cornstarch to the mixture has a chemical reaction to the hydrogen peroxide. It will have light and dark patches due to the uneven placement of the cornstarch; it will have an uneven reaction. Which will then make it appear “glowing”. The fourth experiment is very similar when it comes to the ingredients the only thing that changes is that we are no longer using potassium iodide but we are using yeast instead. Also, since yeast is being used, we are adding in fluorescent dye to it so we can shine a UV (ultraviolet) light on it to see the reaction occurring. Using the dye under a light helps us observe the reaction between the dye and cornstarch. I had to replace the potassium iodide with yeast for a slow reaction and also so it is possible to use the dye. In both of these experiments the reaction is a massive production of foam. The hydrogen peroxide will be decomposed into water and by the oxygen by the iodide and/or the yeast. A substance called catalyst speeds up the
We were able to examine the DNA or RNA by placing the contents in an agarose gel buffers utilizing an electric charge. The process uses restriction enzymes which cut DNA at restriction sites. The process pushes negatively charged particles to the positive pole.
Fluorescein belongs to the group of triphenylmethane dyes with a xanthene structure. Its fluorescence is based on the oxygen withdrawing groups and the intermittend double bounds shifting the wavelength towards the visible light range. Radicals can distubr this structure and erase the fluorescence by destructing one aromatic ring structure as seen in the reaction scheme.
The results from the gel electrophoresis were inconclusive so students selected their genotype, with the results shown in Table 1. The controls were successful with the (+/+) homozygous, (-/-) homozygous, and heterozygous lanes having bands at 941, 641, and both 941 and 641 respectively. The class allelic frequencies were 56.3% for p and 43.8% for q, indicating that slightly more individuals had the Alu insert on their chromosomes (Table 2). When the Hardy-Weinberg equation was applied, there were some discrepancies as shown by Table 3 between the observed and calculated frequencies. The p frequency was observed at 10% higher than Hardy-Weinberg while the q frequency was observed at 10% lower.