Measuring the Effectiveness of Various Antacids

1. Measuring the Effectiveness of Various Antacids Gabrielle cArlini

2. Purpose • To discover which brand of antacid is the most effective in treating GERD • To study the effects of adding hydrochloric acid to different brands of antacids in order to determine which would resist the pH change

3. Background Information • Antacids are agents that neutralize stomach acid. • Each type of antacid works differently depending on its main ingredients. • Hydrochloric acid is the key component of stomach acid. It has a pH of about 2. • Gastroesophageal reflux disease, most commonly referred to as GERD, is a common and usually short-term stomach condition. • Antacids are the most common medication, because they can weaken the acid until the esophagus closes on its own.

4. Hypothesis • Because calcium carbonate (Tums), has the highest pH of the antacids being tested, it will neutralize the most acid.

5. Materials • Burette (1) • ring stand (1) • Milk of Mylanta (750mg) • Alka-Seltzer (750mg) • Tums (750mg) • Maalox (750mg) • pH probe and the corresponding software • Computer • HCL (240mL) • water • mortar and pestle • Funnel (1) • gloves

6. Procedure • 1. Dissolve 250mg of Alka-Seltzer into 12mL of water and pour into a beaker. Put the beaker underneath the ring stand. • 2. Pour 20mL of hydrochloric acid into the burette and attach it to the ring stand. • 3. Set up the pH probe and place it into the solution. It should read around 9. • 4. Slowly add the acid to the base, one mL at a time. • 5. Record the pH after each mL, until the acid has all been titrated. • 6. Repeat 2 more times, then do the same for each other antacid.

7. Variables • Independent • type of base used • Dependent • pH of the solution • Control • because this experiment was a comparison, there was no control group

8. Data (I)

9. Data (II)

10. Data (III)

11. Conclusion (I) • It was revealed that not all bases resist pH change the same way. • The aluminum-magnesium hydroxide and magnesium hydroxide kept the starting pH relatively high because they were very strongly basic. • The sodium bicarbonate and calcium carbonate didn’t start with very high pH’s, but resisted the acid to the point that even after 20mL were added, the solutions were barely acidic. • The original hypothesis was partly proved, but it was also learned that the level of the pH is not the only factor determining the antacids’ effectiveness. • Antacids that use ingredients such as sodium bicarbonate and calcium carbonate are much more effective at treating GERD, because they are able to keep the pH level in the stomach higher for longer, resulting in a less painful condition.

12. Conclusion (II) • Sources of Error • Some of the antacids were solid and had to be dissolved with water; which may have affected the overall pH. • Some of the antacids contained ingredients other than the main active ingredient which may have interacted with pH level.

13. Works Cited • Antacids. (2011). Retrieved from drugs.com website: http://www.drugs.com/‌drug-class/‌antacids.html • a good basic definition of an antacid • Antacids and Acid Reducers. (2010, December 15). Retrieved from WebMD website: http://www.webmd.com/‌a-to-z-guides/‌nonprescription-medications-and-products-antacids-and-acid-reducers • describes types of antacids and how each one works • Bishop, M. (2010). Titration. Retrieved from http://preparatorychemistry.com/‌Bishop_Titration.htm • a great procedure for a basic titration (provides many details) • Clark, J. (2002). pH/‌Titration Curves. Retrieved from ChemGuide website: http://www.chemguide.co.uk/‌physical/‌acidbaseeqia/‌phcurves.html • a good guide for pH and titrations, helps clear up some of the harder language and key terms • Gastroesophageal reflux disease. (2011). Retrieved from US National Library of Medicine website: http://www.ncbi.nlm.nih.gov/‌pubmedhealth/‌PMH0001311/ • complete description of GERD, explains why antacids are needed • Gbemudu, A., PhD. (2011). Information on Antacids. Retrieved from Rx List Inc. website: http://www.rxlist.com/‌script/‌main/‌art.asp?articlekey=95545 • complete description of everything needed to know about antacids • GERD, Heartburn, and Acid Reflux. (2009). Retrieved from RelfuxDenfense System website: http://refluxdefense.com/‌heartburn_GERD_articles/‌introduction-causes-and-symptoms.html • over view of GERD and recent research on why antacids may not be the best medication • Hazardous Materials. (2008, December 30). In ES&H Manual (pp. Chapter 40) [Pamphlet]. Retrieved from http://www-group.slac.stanford.edu/‌esh/‌eshmanual/‌references/‌hazmatGuideHydrochloricAcid.pdf • complete description of how to obtain, handle and dispose of hydrochloric acid • Purchon, N. D. (2006, November 10). pH. Retrieved from http://www.purchon.com/‌chemistry/‌ph.htm • a basic overview of what pH is • Stomach Acid. (2008). Retrieved from Digestionquestions.com website: http://digestionquestions.com/‌gerd/‌stomach-acid.html • complete description of the chemical composition of stomach acid • Tullmin, M. (2002). History of pH. Retrieved from M. Tullmin website: http://www.corrosion-club.com/‌historypHscale.htm • history of pH • What is pH? (2007, June 8). Retrieved from Environmental Protection Agency website: http://epa.gov/‌acidrain/‌measure/‌ph.html • another overview of pH