The Quantitative Determination of an Acid in
Carbonated Beverages
Thomas Canfield
Kelly Caddell
Chemistry 144B
T.A. Brock Marvin
15 October 2012
Methods: Two sodas containing citric acid were investigated in this experiment. Each soda was titrated using one of the two experimental methods. These methods are the traditional titration and the modern titration. Carbonic acid was already removed from the soda by boiling it. Both of the two different titration methods use the same basic set up. Firstly, the buret must be cleaned thoroughly with tap water. While cleaning the buret, it is also checked to make sure there are no leaks. The ring stand is then set up with a buret clamp and the cleaned buret placed in it. Then the buret is filled with 5-10mL of sodium hydroxide, M .0466 NaOH, three times and emptied after each time to completely rinse the buret. The buret is now filled will NaOH until it reads at the 0.00mL mark on the buret. The initial volume of NaOH in the buret is then recorded into lab books for future reference. The soda must now be readied for titration. Both sodas require the same set up. The correct amount of soda, depending on which titration, is poured into a 100mL graduated cylinder. This measurement had to be within 5% deviation of the given value to be legitimate. Next, after the initial volume of the soda was recorded for future calculations, distilled water was added up to the 100mL mark on the cylinder. The mixed solution was then put into a 250 mL Erlenmeyer flask. That is as far as the similarities between the two titration methods go. In order to prepare the first soda for the traditional titration, five drops of phenolphthalein dye are added to the soda water solution in the flask. Next, the tip of the buret was placed over top of the soda solution. NaOH solution was added at approximately 2mL increments. The dye will create a pink color that disappears when mixed. When the