2-Methylbutane Lab Report

During the halogenation reactions of 1-butanol, 2-butanol, and 2-methyl-2-propanol, there is a formation of water from the OH atom of the alcohol, and the H atom from the HCl solution. The OH bond of the alcohol is then substituted with the Cl atom. Therefore all of the degrees of alcohol undergo halogenation reactions, and form alkyl halides as products. This is because the functional group of alkyl halides is a carbon-halogen bond. A common halogen is chlorine, as used in this experiment.

In the first acid extraction of benzocaine, the compound was dissolved in the organic solvent of dichloromethane. When the mixture was shaken with HCl, benzocaine’s amine group gained a proton and became more soluble in water than dichloromethane. This allowed the newly formed hydrochloric salt to migrate to the aqueous layer. However, the addition of NaOH to the acidic aqueous layer regenerated benzocaine by deprotonation, making it insoluble in the aqueous layer. The precipitation of an ionic salt was therefore recovered by vacuum filtration and had a tested melting point range of 85.1C-87.4C compared to 88C-90C, the literature melting point of benzocaine. The similarity in melting point ranges, but low percent yield of 30.37% proves that the extract was somewhat successful. Lower yields may be the result of spillage performed in the lab. In the second basic extraction, the organic layer now included benzoic acid and benzamide. When treated with NaOH to deprotonate benzoic acid, the newly formed sodium benzoate transitioned to the aqueous layer as a sodium salt. Benzoic acid is regenerated once again after the addition of HCl and became insoluble in the aqueous layer after protonation. Its precipitation was then filtered out for a 65.87% recovery. Compared to its literature melting point of 122.41C, the resulting 120.9C-123.5C melting range of the sample also supports the accuracy of the separation due to its similarities and high percent yield. In conclusion, the usage of base and acid liquid extraction was mostly successful in this experiment because it was able to efficiently and properly isolate the impure mixture into two separate components of benzocaine and benzoic acid. By performing the techniques of extraction and vacuum filtration, the similarities between literature and tested

The crude product was washed by taking the reaction product in the separatory funnel and adding 23 mL of deionized H2O. The mixture was shaken and allowed to settle until layers were observable. The top layer was the desired product and approximately 25 mL of aqueous layer was extracted from the separatory funnel. Next, 25 mL of 5% NaHCO3 was added to the separatory funnel in order to neutralize the acid. This mixture was swirled, plugged with the stopper and inverted. Built-up gas was released by turning the stopcock to its opened and closed positions, releasing CO2 by-product. This was done four times in one minute intervals. The solution was allowed to settle until layers were observable. The bottom layer that contained salt, base and water was extracted from the separatory funnel. The crude product was washed again as mentioned previously.

A unimolecular nucleophilic substitution or SN1 is a two-step reaction that occurs with a first order reaction. The rate-limiting step, which is the first step, forms a carbocation. This would be the slowest step in the mechanism. The addition of the nucleophile speeds up the reaction and stabilizes the carbocation. This reaction is more favorable with tertiary and sometimes secondary alkyl halides under strong basic or acidic conditions with secondary or tertiary alcohols. In this experiment, the t-butyl halide underwent an SN1 reaction. Nucleophiles do not necessarily effect the reaction because the nucleophile is considered zero order, (which makes it a first order reaction.) The ion that should have the strongest effect in an SN1 reaction is the bromide ion. The bromide ion should be stronger because it has a lower electronegativity than chloride as well as a smaller radius.

Approximately 0.05 g of 9-fluorenol, 250mg of chromic oxide resin, and 2 mL of toluene were used for the reaction solution. The CrO3 resin consisted of little brown solid balls. The reaction solution was slowly heated to 130°C. The reaction solution slowly turned light yellow as it was being heated. 1M standards for 9-fluorenol and 9-fluorenone were used. The reaction mixture had a strong gas-like odor while it was filtered through the Hirsch funnel. After evaporating the solvent using a rotary evaporator, the crude product that was left was yellow and solid. When hexane was added the yellow solid formed into a yellow liquid.

The aim of this report is to come to a conclusion of which of the selected fuels is best for camping (no wood is available). The best fuel will be determined by safety and heat of combustion. There will be three fuels selected to experiment with are Pentane, 1-Propanol and 2-Propanol.

Hydrogen Peroxide, otherwise know as H₂O₂ is the simplest of all the peroxide chemicals known to man. Hydrogen Peroxide is base that is used in many reactions to create other more complex peroxides, it is used as an oxidizing reactant in these cases. It is created in 4 steps. Step 1, Palladium catalyses the reaction between H₂ and anthraquinone to create anthrahydroquinone (H₂Q):

When we added the 1% silver nitrate to the alkyl halides in the first part of the experiment the first two test tubes, containing 2-bromo-2-methylpropane and 2-bromobutane, became cloudy almost immediately. The 2-bromo-2-methylpropane and 2-bromobutanes’ cloud was light green in color. The 1-bromobutane precipitated, though more slowly than the first two tubes, and its cloud was white. We also noticed that the 1-chlorobutane never seemed to become cloudy or precipitate. This is likely because chloride is a worse leaving group than bromide is (due to the chloride anion being a smaller ion, it can’t “handle” the negative charge as well as the larger bromide anion, so it doesn’t want to leave the carbon it’s sharing the electron with in 1-chlorobutane).

To find the percent yield, the theoretical yield was calculated by using the stoichiometric ratio of the reactants, and the experiment was performed to find the actual yield. When the CaCl2 and NaHCO3 were mixed together, there was fizzing and bubbling that eventually led to a milky, chalky, white color. With the fizzing and bubbling, it was inferred that gas was released. As a result, a solution of calcium carbonate product formed. As the solution passed through the filter, layers of solid, white, calcium carbon built on top of each other and a cloudy filtrate appeared. Clearly, the microcrystal calcium carbonate suspended onto the filter. Additionally, because some of the product was too minuscule, it passed through the filter and less product was made (which means that the percent yield should be lower than 100 percent).

The spectrometer was calibrated using a “blank” cuvette of methanol and then the absorbance and the wavelength for each dye was measured. Each dye was diluted tenfold several times with methanol until the max wavelength peak had an absorbance less than 1. All three dyes needed to be diluted 3 times before they were at the correct concentration to measure the maximum wavelength. As each dye was diluted the colors of the dyes became more faded and also a lighter shade, for example 1-1’-diethyl-2-2’-cyanine iodide, which was red initially became a shade of pink. The initial colors observed for pinacyanol chloride was blue and 1-1’-diethyl-2-2’-dicarbocyanine iodide was green. Graphs of the absorbance versus wavelength (nm) for all three dyes

Extraction is defined as a process for separation of compounds in a mixture based on difference in their solubility. Extractions have been in use for centuries, and there are many

The melting point helps determine the identify of the solid product obtained from the experiment. By using the Mel-Temp machine, the solid’s melting point can be determined when the solid melts into a liquid. The experimental melting point of the diphenylacetylene was found to be 46 degrees Celsius. The actual melting point of diphenylacetylene was 62.5 degrees Celsius. Therefore, there was a 16.5 degrees Celsius difference between the experimental and the actual melting points and the experimental was much lower.

The liquid extraction was done by using three batches of methylene chloride of 25 ml each. The solution was passed through a funnel containing sodium sulfate and wool to absorb any possible contaminants and water residue. After this procedure was performed several small boiling chips were added to the round flasks and the solution was then evaporated to a very small volume. The solution was then transferred to concentration tubes and further evaporated to a volume of 1 mL by constantly adding a solution of hexane so that all of the methylene chloride was replaced. As a final step, 50 µl of TMX and OC standard were added to the extraction

As the distillate was obtained from the steam distillation, several liquid-liquid extractions with methylene chloride were performed in separatory funnels to separate the aqueous water layer from the organic layer. The formation of two distinct layers occurred because the two liquids are immiscible and will not mix together because of their solubility and density differences. The organic methylene chloride layer formed the bottom layer, because it is more dense than water forcing the aqueous water layer to the top. The organic layer at the bottom was dispensed into a flask, leaving the aqueous layer in the funnel to perform two additional washes. The next extractions were done using ether and the remaining organic layer liquid from the flask. Ether is less dense than water so the organic ether layer formed the top layer and the aqueous layer formed at the bottom.

As observed in both experiments and simulations, at 2 atm, DME can slightly inhibiting effect on n-pentane ignition, while at 10 and 20 atm, DME addition did not obvious influence n-pentane ignition. To further understand this phenomenon, reaction pathway analysis of DME, 50%DME/50% n-pentane and n-pentane were conducted at 20% fuel consumption using NUI Galway pentane isomers model.