Purpose:

To determine which antacid will neutralize the most acid for the best price.

Materials:

- antacids (Tums, Life Brand, Gavison, Alka-Seltzer)- graduated cylinder- concentrated HCL- pipette- mortar and pestle- methyl orange indicator- Erlenmeyer flask (125ml)- glass stirring rod- distilled water

Observations:

Table 1: The number of drops required to neutralize a half tablet of each antacid.

Antacid Type Number of Drops until Neutralized

Tums - Regular 130

Alka-Seltzer - Fast Relief 175

Life Brand 105

Gaviscon - Max Relief 10

Discussion Questions:

Question 1:

The Antacid that was the best choice by amount of acid neutralized was Alka-Seltzer - Fast Relief. The reason Alka-Seltzer - Fast Relief was the best choice by amount of acid neutralized is because it neutralized the most amount of acid com-pared to the other choices at 175 drops for half a tablet.

Question 2:

The most Cost effective choice given the neutralization results is Tums because it neutralized the 2nd highest amount of acid and is the 2nd lowest cost at $0.04/tablet.

Question 3:

1) Calcium carbonate: CaCO3 + 2HCl -------> CaCl2 + H2O + CO2

2) Sodium bicarbonate: NaHCO3 + HCl ------> NaCl + H2O + CO2

3) Magnesium carbonate:MgCO3 + 2HCl ------> MgCl2 + H2O + CO2

Question 4:

We know that all the acid was neutralized as soon as all the orange fluid in the Er-lenmeyer flask changed into a pink colour. As soon as the colour changed pink, the fluid was at number 7 on the pH Scale, and it was neutral.

Question 5:

1) One potential reason for getting different results among groups, is that the half tablets may not have been the exact same mass. If the the half tablets were weighed before they were put in the Erlenmeyer flask, and all groups weighed the same, the lab would be more accurate.

2) Another reason for getting different results among groups could be the size of the HCl drops. Although there is not much difference in drop sizes, they are not all the exact same size. This makes the lab less accurate and may cause different results among groups.

Conclusion:

Alka-Seltzer was ranked most effective, because it took 175 drops to neutralize.

Tums was ranked second most effective, because it took 130 drops to neutralize.

Life Brand was ranked third most effective, because it took 105 drops to neutralize.

Gaviscon was ranked least effective, because it took 10 drops to neutralize.

The best choice of antacid is Tums, based on neutralization results and cost. Tums is the best choice of antacid because it is effective, and it is a good price. Tums are effective because it takes 130 drops of HCl to neutralize it. It is not only effective, but it is also the second lowest price of these four antacids at 4 cents per tablet. It is only one cent more expensive than Life Brand at 3 cents per tablet, and takes 25 more drops to neutralize it than Life Brand does. Alka-Seltzer takes 45 more drops to neutralize it, however it is 20 cents more expensive per tablet. Gaviscon is 49 cents more expensive per tablet and is not very effective, and only take 10 drops to neutralize it. This is why the best choice of antacid is Tums, based on neutralization results and cost.

Testing AntacidsMichael Wright, Grade 10 Science - Mr. Anderson, March 20th 2013