Authors: Alexxis Harris Constance Doty Brandon Hokenson Gavin Hunt Melissa Munoz
Affiliation: Department of Chemistry, University of Central Florida
Abstract
The purpose of this experiment is to identify which antacid is the best at neutralizing stomach acid. Antacids are commonly used self-prescribed medications. The stomach produces hydrochloric acid, which has a range of pH (1.5 to 3.5). Several antacids such as Gelusil, Alka Seltzer/effervescent, Alcalak, and Medi-first were indirectly titrated with sodium hydroxide (NaOH), which is a strong base. By using the back titration technique, the amount …show more content…
The following materials were gathered for the experiment: mortar and pestle, 50 mL titration burette, clamp stand, 250 mL beaker, 100 mL volumetric flask, filter paper, 10 mL bulb pipette, and five 50 mL beakers. After the titration burette was set up in the clamp stand, 50 mL sodium hydroxide (NaOH) with a concentration of 0.25 M was poured into the titration burette. The weight of the Gelusil tablet in the original form (whole) was recorded (1.41 grams). A mortar and pestle was used to crush the Gelusil tablet. Next, the weight of the crushed Gelusil tablet was recorded (1.28 grams). A 150 mL beaker was filled with hydrochloric acid, which had a concentration of 0.15M. The crushed Gelusil tablet was poured in a 100 mL volumetric flask by using a piece of filter paper as a funnel. Subsequently, hydrochloric acid was added into the 100 mL volumetric flask as well. After combining the Gelusil tablet and hydrochloric acid, the volumetric flask was shaken (with a thumb covering the top) to ensure …show more content…
Ever so often, the thumb was removed to allow carbon dioxide to release from the reaction. A bulb pipette was used to displace 20 mL of the Gelusil and hydrochloric solution into five 50 mL beakers. Then, two drops of phenolphthalein (color indicator) was added into each of the beakers. Each 50 mL beaker (that contains Gelusil, hydrochloric acid, and phenolphthalein) was placed at the endpoint of the titration burette and had sodium hydroxide added into the beaker until the solution appeared a medium pink. The amount of sodium hydroxide added to each beaker of solution was