The hypothesis is that this acid is CHOOSE. Experimental Procedure for melting point: The identification of the melting point of the organic acid was done to find another characteristic of the acid and to test the purity of the reestablished pure acid. A 2-4 mm layer of unknown sample was placed into a capillary tube sealed on one end. Then the capillary tube was inserted into the side a Bibb Sterling device. The plateau was set to ICC on the melting point apparatus. Once the plateau temperature was reached, the sample was watched carefully.
When the sample first began to melt and when it was fully melted was recorded. These numbers were the range of the melting point. A slow melting point of the unknown organic acid and a standard sample was completed next. A new plateau was set about ICC lower than the observed melting point of the unknown sample. This time once the plateau was reached, the heating was no more than OIC per minute. This gave a much more accurate read of both melting points. If the standard did not melt in the range listed on the label of the bottle, that meant the machine was not working properly.
The standard sample and the unknown organic acid melted in their appropriate ranges. Procedure for equivalent weight: A sodium hydroxide solution was prepared. Then 4. 2 ml of concentrated 19. 1 M Noah was obtained and mixed with 800 ml 20th in a IL bottle. Approximately 0. 3 g of KIP was weighed on an analytical balance. The KIP was poured into a 250 ml Erlenmeyer flask and titrated with the Noah solution. Two to three drops of phenolphthalein indicator was placed into the flask. The malarial of Noah was calculated by using the molar mass of KIP. The molar mass of KIP is 204. 24 g/mol.
The next step was to titrate using HCI. HCI titration are mainly to check technique and used to verify the malarial of Noah solution. First, 60 ml of 0. 2 M HCI solution was obtained. Then 10 ml of WHQL was transferred to an Erlenmeyer flask. One drop of indicator and 50 ml of denizen were added to the flask. The solution was titrated using Noah. Finally, a titration using the unknown sample was completed to determine equivalent weight. Approximately 0. 3 g of unknown was weighed on an analytical balance. The unknown sample was then dissolved using 10 ml of ethanol and 10 ml of denizen water.
The solvent combination was poured into an Erlenmeyer flask and titrated with Noah. Three trials were completed for each titration. Procedure for data search: Because of the previous determination of the melting point and the average equivalent weight of the unknown, there was enough information to do a computer search. A melting point was entered into the database with a ICC deviation and the equivalent weight had a 15 g deviation. The computer search listed three possible choices for the unknown organic acid: benzene acid, furan-2- carboxylic acid, and dedication acid isobaric acid.
Procedure to determine peak: Three peak experiments were completed because none of the organic acids on the computer search results contained halogens. Approximately 0. 2 g of the unknown sample was weighed using an analytical balance and put into a 250 ml beaker. In the first trial, a solvent combination of 50 ml of denizen water and 50 ml of ethanol was used. A beret was filled with Noah and the initial volume was recorded to two decimal places. Next, the pH meter was calibrated. The pH meter was rinsed and dried, then placed into the 250 ml beaker.