Since alkenes are immiscible with concentrated HBr, tetrabutylammonium bromide is used as a phase-transfer catalyst. It forms a complex with HBr and extracts it from the aqueous phase into the organic phase where the alkene is. This dehydrates the acid, making it more reactive so that the addition reaction is possible. Rapid stirring is required in order to maximize the surface area
It is faster due to the filter funnels surface area. Results/Observations Experimental data resulted as expected because it was found that on experiment one, Benzoic Acid could recrystallize with a better recovery percentage than the solvent pair in experiment two. The mass recovered in experiment one was 0.048g while experiment two had a mass recovery of 0.045g. Solvent(s) Used Mass of “Crude” (g) Mass of Recovered (g) Amount of Solvent Used (mL) Percent Recovered (%) Experiment One Water (H2O) .051 .048 1.0 94.1 Experiment Two Methanol (MeOH) And Water (H2O) .049 .045 Methanol – 1.5 Water – 0.5 92 Conclusion Both experiments were of fair solubility, but in the case of recrystallization of Benzoic Acid, Water was the best solvent to recrystallize acid the most. Experimental data determined that there was a difference of .003g between using the single solvent in comparison to the paired solvent.
This would have made the results less accurate and made any errors change the final results even more. To make sure this doesn’t happen, there needs to be more trials to increase the precision of the results. Abstract The purpose of the lab was to determine what each of nice substances was based upon how they reacted with other chemicals as well as their pH levels. By using the given clues, the reaction with Litmus paper, and the precipitates formed by different mixtures, the chemicals were identified. Substance 1 was found to be BaCl , substance 2 was determined to be NaOH, and substance 3 was labeled as CuSO .
Solvent used in the elution process would be the mobile phase and solvents of different polarity would have a significant impact on the separation due to the varying solubility of compounds in different solvents. Hexane, being the less polar solvent, interacts mainly with the less polar analytes but very slowly with polar analytes. Therefore using hexane at the start of the elution process allows the less polar compound to be eluted out first. After the complete collection of less polar analyte, the mobile phase was changed to the more polar hexane/ethyl acetate solvent, which has stronger interaction with the more polar component, allowing it to be eluted out faster. The change in solvents throughout the elution process would allow for an effective and efficient separation of the compounds β-carotene and chlorophyll in the crude extract of green leaves.
Sodium Bicarbonate mixed with Hydrochloric acid. The chemical reaction observed showed that there was fizzing and bubbling, this is evidence that a new gas was being produced. This new gas, CO2 was generated from the reaction. After the fizzing stopped a liquid was leftover leading me to conclude the liquid leftover leading me to conclude the liquid leftover was the NaCl and H2O 4. You found a sample of a solution that has a faint odor resembling vinegar (an acid).
Chemical reactions transform bond energy into heat or work. Enthalpy of reaction (Hrxn) is the term used for the change in heat as a reaction is carried out at constant pressure. It is a state function as it only depends on the final and initial conditions during the change of state. If Hrxn < 0, the system releases heat and is therefore an exothermic reaction. On the other hand, if Hrxn > 0, the system absorbs heat.
Moreover, it acts as dehydrating agent, forcing the equilibrium to the products and lead to a greater yield of ester. After the addition of trace amount of concentrated sulfuric acid, the reactant flask is heated so that the reaction can be speeded up and ester can be obtained faster. The reason of adding concentrated drops-by-drops into the reactant flask and swirl the flask while adding the acid is to prevent any part of the mixture getting too hot and reacting to form unwanted darkly coloured by-product. Before the heating of the liquid, boiling chips is added inside the reactant flask to allow a nucleation site for gradual boiling and avoid a sudden boiling surge where may cause the liquids inside the reactant flask to overflow or spill out as it has
It was previously mentioned that the focus of this study is to use ceria-zirconia (CeO2-ZrO2) as the catalyst support. The approach of A. Poyraz et al.  to synthesize varying ratios of CeO2-ZrO2 mesoporous materials was modified and used. The modifications were the following: (a) zirconium (IV) oxynitrate hydrate was used instead of zirconium (IV) butoxide; (b) application of the method for the synthesis of CeO2-ZrO2 solid solution; and (c) physical separation of solids (filtration instead of centrifugation). Cerium nitrate hexahydrate (Ce(NO3)3∙6H2O), zirconium (IV) oxynitrate hydrate (ZrO(NO3)2∙xH2O), 1-butanol, nitric acid (HNO3) and P123 surfactant (EO20-PPO70-PEO20) were the required chemicals.
In this experiment, Analysis of Gaseous Products, a comparison between the elimination reactions created in the presence of an acidic and basic conditions was observed to be further analyzed through gas-liquid chromatography. These conditions were achieved by acid-catalyzed dehydration of a secondary and primary alcohol and based-induced dehydration of a secondary and primary bromide. As a result of these changing eliminations, gas-liquid chromatography makes it possible to separate and isolate volatile organic compounds to analyze the stereochemistry and regiochemistry of these compounds without decomposing them. Overall, gas-liquid chromatography of these compounds in acidic or basic conditions contributed in the identification and analysis
Chromatography means of separating and tentatively identifying the components of a mixture. Gas chromatography separates mixtures on the basis of their distribution between a stationary liquid phase and a mobile has phase. In GC, the moving phase is actually a gas called carrier gas, which flows through a column. The stationary phase is a thin film of liquid contained within the column. After a mixture has traversed the length of the column, it emerges separated into its components.