Separation of a three-component organic mixture using extraction techniques and acid-base chemistry chemistry 233: organic lab i august a gallo and jimmy d fitzpatrick department of chemistry benzoic acid which is insoluble in h2o,. Chem 233: organic laboratory i prelab lecture university of illinois at chicago uic o h2o protonation + r nh2 o + r nh3 h oh2 o h2o na oh oh h n amine (conjugate base) ammonium cation (conjugate acid) o crude solid: • not pure/clean • depressed mp • possibly discolored ch2cl2 lab 6: base extraction of benzoic acid from acetanilide followed by recrystallization and mp determination. Goal: the goal of this lab is to separate benzoic acid from a mixture containing benzoic acid, cellulose (a natural polymer of glucose) and methyl orange (a common acid/base indicator) you will use a chemically active extraction to convert the water insoluble benzoic acid into its water soluble salt by treating the carboxylic acid with base. This is often times called the lattice theory you should read the section on recrystallization in the oclsm which begins on page 103 goal: the goal of this week's lab is to recrystallize the benzoic acid you isolated last week you will also determine the % recovery for the recrystallization you carry out.
A mixture containing p-bromoaniline, benzoic acid, and phenanthrene is separated using acid-base extraction closed captions available chemistry lab at eastern kentucky university, us. Benzoic acid 11 56 55% 120-128 1224 benzil 129 56 43% 96-98 944 mixture n/a n/a n/a 80-113 114 table 1 the crude benzoic acid was a white powdery substance that weighed 11 grams the pure benzoic acid that was recrystallized was white crystals weighing 56 grams. Standard solutions that are used for extraction are: 5 % hydrochloric acid, 5 % sodium hydroxide solution, saturated sodium bicarbonate solution (~6 %) and water all of these solutions help to modify the (organic) compound and make it more water-soluble and therefore remove it from the organic layer. The actual laboratory we will do is the recrystallization of benzoic acid from water using the temperature gradient method benzoic acid is not very soluble in cold water, but it is soluble in hot water the purpose of this experiment is to learn the technique of recrystallization by purifying benzoic acid.
Laboratory 5 extraction concept goals: correlation of structure, polarity, acid and base characteristics and extraction is a technique that selectively dissolves one or more of a mixture of compounds into an appropriate solvent in this experiment you will use the common technique of liquid-liquid extraction to separate and purify benzoic. Considering that the melting points of the benzoic acid was exactly the same as the book value for benzoic acid (according to g & m) and the melting point for the extracted 2-naphthol was 121 0 c, which is 16% different than the book value of 123 0 c since the benzoic acid and 2-naphthol samples were considerably pure, the impurities in the. In this experiment you will use extraction techniques to separate a mixture of an organic acid, a base, and a neutral compound organic acids and bases can be separated from each other and from neutral compounds by extraction using aqueous solutions of different ph values. In today’s experiment benzoic acid and 2-naphthol will be separated by employing an acid-base extraction technique using the bases sodium bicarbonate and sodium hydroxide. Extraction: separation of acidic substances notes authors: j sevenair, s l weaver (benzoic acid and 2-naphthol) dissolved in an organic solvent, mtbe (methyl t-butyl ether) below are all the possible reactions for the lab examine each reaction, assign acid and base to each compound, determine if the reaction will proceed in the.
Acid-base reactions favor the side with the weaker acid (that is, they favor the side with the larger pka) so, extracting a mixture of these two compounds with bicarbonate results in the ionization and extraction of a carboxylic acid in the presence of phenol thus separating the two compounds from one another. The benzoic acid is precipitated from the alkaline solution on acidifying with hydrochloric acid and purified from hot water yielding final product with melting point 121° c the practical methods of organic chemistry, by l gattermann, 274-275, 1909. Benzoic acid has a carboxylic acid functional group, which makes it an acidic compound, while 1,4-dimethoxybenzene has two ether groups and is neutral benzoic acid will react with a base like sodium hydroxide to create sodium benzoate, which is soluble in water. Chart 1 - flow of benzoic acid, phenol, aniline, and naphthalene in ether 5 siavosh naji-talakar lab report 4 10-2-15 6 siavosh naji-talakar lab report 4 10-2-15 procedure benzoic acid and naphthalene were massed out to around 0100 grams each using the digital scale.
The purpose of this experiment is to separate a prepared mixture of benzoic acid, 4-nitroaniline, and naphthalene by the technique of extraction the compounds will be extracted on the basis of the solubility properties of the acids, bases, and their salts. Of benzoic acid in dichloromethane extraction is a separation technique frequently employed in the laboratory to isolate one or more components from a mixture. The conjugate base of the acid is the first part to be recrystallized with a concentrated, strong acid- in this case hcl- to protonate the conjugate base to make a benzoic ring, which is insoluble in water (reaction 3.
There is no any observable benzoic acid in second conical flask which means the majority of benzoic acid was extracted in first conical flask after extraction, the percentage yield of benzoic acid was 1308. 11 experiment 2: recrystallization and melting point experimental procedure: (refer to zubrick text for additional details) recrystallization: using a hot plate, dissolve approximately 10 g of impure benzoic acid in 30 – 35 ml of hot water (water at or near its bp) in a 125 ml erlenmeyer flask. Extraction of benzoic acid 1 abstract the purpose this experiment was carried out was to determine the overall mass transfer coefficient of benzoic acid between kerosene and water. Experiment 3: acid/base extraction and separation of acidic and neutral substances introduction in today’s lab, we are adding a base to form an ionic salt from the organic compound, which will make it water soluble to separate it from the (benzoic acid) and the phenol (2-naphthol) and both will dissolve in the aqueous base,.