Antacid Lab Report

Introduction

Results

Conclusions

Maria Martello, Caroline Seelman, and Keely Culbertson

December 8, 2016

Humans often get sick simply because our bodies cannot fight off everything; sometimes these illnesses are grave and fatal, but sometimes these illnesses can result in something that can be treated such as a stomach ache. For these easy fix sicknesses, we have antacids. When acids and bases come in contact, they neutralize each other (3). Antacids are bases therefore they neutralize the acid in your stomach which is hydrochloric acid (1).

In stores, antacids will be known as Tums, Rolaids, Gaviscon, Mylanta, or simply store brand generic antacids. With different brands, it is important to determine which is more effective at neutralizing the hydrochloric stomach acid in your body.

My lab group decided to take a commonly used brand, Rolaids, and come it to the generic Walgreens brand of antacids. My prediction was that Rolaids would be more effective at neutralizing acid because it is associated with a name brand.

To test the difference between Rolaids antacid and Walgreens antacid, we took both tablets and put them in hydrochloric acid and measured the pH value. Antacids are effective because they are weak bases, but what makes them effective is their active ingredient which is the actual bases that is doing the neutralizing (3). The active ingredient that we used in our lab was Calcium carbonate (CaCO3) (2). Since the pH value should correlate with how much of the antacid was dissolved, we gave both tablets the same amount of time to dissolve before we measured their pH values. The strength of the antacid is also very important to its pH value, so we decided to use extra strength for both type of antacid. Using a pH meter, we determined the pH value of each tablet in the hydrochloric acid in 3 trials for each brand.

Materials: 3 Rolaids Extra Strength tablets, 3 Walgreens Extra Strength tablets, pH meter, 0.1 M hydrochloric acid, 2 50 mL beakers, 1 mortar and pestle, 2 glass stir-rods, goggles, 50 mL graduated cylinder

Method: Our lab group took a Walgreens tablet and crushed in the mortar and pestle until it’s texture was almost powdery. We filled a beaker with 25 mL of hydrochloric acid and tested the acid’s pH level. We then poured the crushed up tablet into the hydrochloric acid and mixed the solution for 3 minutes. After 3 minutes, we tested the pH level of the solution. We repeated this process two times with the other two Walgreens tablets. We then took the Rolaids tablet and followed the same process for 3 trials.

The purpose of this experiment was to compare the effectiveness of different drugstore antacids. To determine which type of antacid neutralized more stomach acid, we gave both tablets time to dissolve in hydrochloric acid and then measuring the pH. Our experiments were performed accurately because both Rolaids antacid and Walgreens antacid contain the active ingredient Calcium carbonate (CaCO3). We also gave each tablet the same amount of time to dissolve before measuring the pH.

When we observed both tablets, the Rolaids tablet was white, wide, and round, and the Walgreens tablet was colored, wide, and round (Table 2). When we put the Rolaids tablet into the hydrochloric acid, it did not dissolve and it stayed white (Tablet 2). When we put the Walgreens tablet into the hydrochloric acid, it fizzed, became changes colors, and bubbled (Table 2). The Walgreens tablets were colored because of their flavoring. In trial 1, we used an orange tablet so the solution turned orange (Table 2). In trial 2, we used a purple tablet so the solution turned purple (Table 2). In trial 3, we used a yellow tablet so the solution turned yellow (Table 2).

Since humans get sick often and our immune system cannot fight off all illnesses, modern medicine has many temporary remedies for all afflictions. One of the most common problems is a stomach ache or heartburn which can be fixed by taking antacids (1). Antacids today are sold with many different brands such as Tums, Rolaids, Gaviscon, and store brands, and several different active ingredients such as Calcium carbonate, Aluminum hydroxide, Magnesium carbonate, Magnesium hydroxide, and Sodium bicarbonate (2). In these experiments, we used a pH meter to determine the effectiveness of different antacids at neutralizing stomach acid after 3 minutes.

When we measured the pH values of the solutions, the Rolaids antacid pH level got closer to 7 which is neutral on the pH scale, but not quite there (Table 1). The first trial’s pH value was 5.18 which is closer to 7 than the hydrochloric value of 1.29 (Table 1). The second trial’s pH value was 3.13 which is closer to 7 than the hydrochloric value of 1.58 (Table 1). The third trial’s pH value was 3.34 which is closer to 9 than the hydrochloric value of 1.48 (Table 1). None of the Rolaids tablets were able to neutralize the hydrochloric acid in 3 minutes.

When we measured the pH values of the solution, the Walgreens antacid pH level reached 7 which is neutral on the pH scale (Table 1). The first trial’s pH value was 7.90 which moved from 1.48 (Table 1). The second trial’s pH value was 7.63 which moved from 1.18 (Table 1). The third trial’s pH value was 7.96 which moved from 1.48 (Table 1). The Walgreens antacid was able to neutralize the hydrochloric acid in 3 minutes. We concluded that the Walgreens antacid was more effect at neutralizing stomach acid faster than the Rolaids antacid.

When the antacids came in contact with the hydrochloric acid, they reacted very differently. The Rolaids antacid did not dissolve in the acid in the 3 minutes of mixing whereas the Walgreens antacid dissolved, fizzed, and produced bubbles (see Table 2). We concluded that this was because the Rolaids antacid takes more than 3 minutes to dissolve in your stomach acid whereas Walgreens antacid begins to dissolve right away.

We set out to test the effectiveness of Rolaids antacid and Walgreens antacid by dissolving the tablets in hydrochloric acid and measuring the pH levels and concluded that the Walgreens Extra Strength antacid was more effective at neutralizing stomach acid faster than the Rolaids Extra Strength antacid. The Rolaids antacid could not neutralize the acid in 3 minutes whereas the Walgreens antacid could (Table 1). Therefore, our initial hypothesis that Rolaids antacid would be more effective at neutralizing stomach acid appears to be incorrect.

However, we want to be cautious by sharing this information because it does not mean that Walgreens Extra Strength antacid is the most effective antacid of all drugstore antacids and is the best to take. There are other brands and strengths of antacids so even though we can conclude that Walgreens Extra Strength antacids are more effective than Rolaids Extra Strength, we cannot conclude that they are the most effective brand of all. More experiments definitely need to be conducted using different brands and strengths of antacids before we can conclude that Walgreens Extra Strength antacid is the superior antacid.

Determining Whether Rolaids Antacids or Generic Walgreens Antacids are More Effective at Neutralizing Stomach Acid

Works Cited

"Antacids | Health | Patient." Patient. EMIS Group, n.d. Web. 30 Nov. 2016.
"Chemistry 104: Analysis of Antacid Tablet." Chemistry 104: Analysis of Antacid Tablet. N.p., n.d. Web. 30 Nov. 2016.
"What Is the Active Ingredient in Antacid Tablets?" Reference. IAC Publishing, n.d.

Web. 06 Dec. 2016.