This paper describes the process by which a three-component mixture was separated and identified. The mixture was separated with the aid of a separatory funnel and various solvents acids and bases. The compound was found to be comprised of meta-nitroaniline, naphthalene, and benzoic acid / 2-napthol. All three of them are organic compounds with melting points in the order they were listed 111-114, 79-82 and 121-122/121-123 °C. the percent yield of each component was also calculated at the end…
In this experiment, the components of “Wellactin A” were separated into sucrose, an unknown carboxylic acid, and an unknown organic neutral compound. The unknown compounds were identified by their melting points and the percent recovered was calculated. First, the sucrose was separated by dissolving the organic acid and the organic neutral compound in diethyl ether. 104.9% was recovered, so that means the sucrose was not entirely pure. The sucrose could have been contaminated by another…
In Experiment 12B we used an umpolung reagent in an umpolung synthesis to synthesize benzoin from benzaldehyde. Umpolung synthesis is a synthetic approach that allows us to switch the identity of a reacting species. For example, the normal chemical reactivity of a nucleophile can be switched to one of an electrophilic compound. Two common agents are cyanide and thiamine (Vitamin B). The mechanisms for both agents are the same. In this experiment, thiamine was used to turn benzaldehyde, an…
this lab was to separate unknown compound 204, composed of an amine, a carboxylic acid, and a neutral component, into each of its three respective states. The unknown compound was separated using microscale separation of acidic, basic, and neutral components by liquid/liquid extraction. Liquid/liquid extraction is a very common method often used in work-ups and allows for isolation of neutral components using acid/base chemistry; this method is extremely helpful in separating reactants and…
reason it is considered to be activating is because of the electron pairs on the ether molecule. Furthermore, the electrons activate the benzene ring which makes it more reactive. On the other hand, if benzoic acid replaced anisole in the experiment, it would act as a deactivating group. Carboxylic acid pulls electrons from the benzene ring acting as a withdrawing group which causes a slower reaction with the increase of stability and decrease in reactivity due to resonance. The electrophile…
ABSTRACT Within this experiment, the use of a bomb calorimeter was required in order to determine the heat capacity of the system through the combustion of three separate trials of benzoic acid. The resulting heat capacity values for each trial were averaged, with a standard deviation found as well. This was then used to work backwards, for a naphthalene trial, in order to calculate the change in energy (∆U) and the change of enthalpy (∆H). The accepted value for the change in enthalpy of…
determination of the pH of a buffer solution and the pKa for of a weak acid Introduction A practical was carried out to show how the Henderson-Hasselbalch equation works and to apply and hone the skills of pipetting, buffer-making, pH-meter use and graphing. The primary goal of the practical was to determine the pKa value of a weak acid. The Ka is an acid dissociation constant, it is a quantitative measure of the strength of an acid in solution. The pKa is defined as the negative log of the…
as central nervous system stimulant (British Pharmacopoeia 2009). • Methyl paraben was generously donated by Arab Pharmaceutical Manufacturing Company. Methyl paraben is methyl-4-hydroxybenzoate, prepared by the esterification of p-hydroxybenzoic acid with methanol. It occurs as colorless crystals or a white crystalline powder. It is odorless or almost odorless and has a slight burning taste (Rowe et al., 2009). Methyl paraben is very slightly soluble in water, freely soluble in alcohol and…
mixture of benzoic acid, p-nitroaniline, and azobenzene charged in a 125 mL Erlenmeyer flask mixed with 50 mL of Et2O. Once dissolved, the mixture is transferred the mixture into separatory funnel and begin acid extraction. 15 mL of 3 M HCl is added to the separatory funnel and inverted until a phase boundary is present. An additional 15 mL of 3 M HCl was then added and inverted again. The aqueous layer was removed through the separatory funnel and placed in a 250 mL Erlenmeyer flask labeled…
The other systems of metabolic pathway II is 4-hydroxy - isopropenyl benzene acted as precursors for the forming of p-hydroxybenzoic acid. Pathway III is the original carbon -carbon cleavage on bisphenol accompanied by oxidation causes the forming of hydroquinone (Fig 4). The similar kind of degradation pathway by bacterial isolates were reported (Zhang et al., 2007 and Janett Fischer…