Untitled Essay Research Paper The purpose of

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Untitled Essay, Research Paper The purpose of this laboratory assignment was two-fold, first, we were to demonstrate the extraction of acids and bases, finally, determining what unknowns were present. Second, we were to extract caffeine from tea. These two assignment will be documented in two separate entities.Introduction: Acid/base extraction involves carrying out simple acid/base reactions in order to separate strong organic acids, weak organic acids neutral organic compounds and basic organic substances. The procedure for this laboratory assignment are on the following pages.3) Separation of Carboxylic Acid, a Phenol and a Neutral Substance The purpose of this acid/base extraction is to separate a mixture of equal parts of benzoic acid(strong acid) and 2-naphthanol(weak

base) and 1,4-dimethoxybenzene(neutral) by extracting from tert-butylmethyl ether(very volatile).The goal of this experiment was to identify the three components in the mixture and to determine the percent recovery of each from the mixture.4) Separation of a Neutral and Basic Substance A mixture of equal parts of a neutral substance containing either naphthalene or benzoin and a basic substance containing either 4-chloroaniline or ethyl 4-aminobenzoate were to be separated by extraction from an ether solution. Once the separation took place, and crystallization was carried out, it became possible to determine what components were in the unknown mixture, by means of a melting point determination. Results Procedure Observations InferenceDissolve 3.05g Phenol Mixture was a golden-

Neutral acid in 30ml brown/yellow color t-butyl methyl ether in Erlenmeyer flask and transfer mixture to 125ml separatory funnel using little ether to complete the transferAdd 10 ml of water Organic layer=mixture aqueous layer=water(clear)Add 10 ml saturated aqueous Sodium bicarbonate NaHCO3 dissolves in solution sodium bicarbonate water. to funnel and mix cautiously with stopper onVent liberated carbon Carbon dioxide gas dioxide and shake the mixture was released three times thoroughly with frequent venting of the funnelAllow layers to separate Layer = H3O +NaHCO3 completely and draw off lower layer into 50ml Erlenmeyer flask 1Add 10ml of 1.5 aqueous NaOH Flask 2 = H3O + NaHCO3 (5ml of 3M and 5ml H3O) to separatory funnel, shake mixture, allow layers to separate and draw off

lower layer into a 25ml Erlenmeyer flask 2. Add additional 5ml of water to funnel, shake as beforeAdd 15 ml NaCl to funnel. Shake Bottom layer is white and NaCl was added to the mixture and allow layers to separate gooey. wash the ether and draw off lower layer, which is layer and to remove discarded organic substances NaOH and NaHCO3 Pour ether layer into 50ml Erlenmeyer flask from the top of the separatory funnel (not allowing any water droplets to be transferred) Flask 3Add anhydrous NaSO4 to ether extract until it no longer clumps together and set it asideAcidify contents of flask 2 Litmus went from Acidification was now by dropwise addition of blue to pink. Flask complete concentrated HCl while 2 = creamy color testing with litmus paper and cool in iceAcidify contents of

flask 1 Litmus went from Acidification was now by adding HCl dropwise blue to pink. Flask complete while testing with litmus 2 = white solution paper and cool in iceDecant ether from flask 3 into a tared flaskBoil ether with boiling chipsDo a vacuum filtration and Solution turns to a Crystallization is now recrystallize ether by dissolving it solid. complete in 5ml, taking out boiling chips, adding drops of Ligroin until the solution was cloudy and cool it in iceIsolate crystals from flask 2 by Crystals = creamy-white Dried crystals are now vacuum filtration and wash with powder ready for melting point a small amount of ice water determination and recrystallize it from boiling waterRepeat the above for flask 1 Crystals = white powderFlasks number 4 and 5 were done by the