Chemistry Summative Lab
Testing Antacids
Preamble: Did you know that your stomach produces between 1 and 2 litres of gastric juice every day? The main constituent
in this juice is hydrochloric acid, and the pH of a normal stomach is about 1.5. The purpose of this very acidic medium is to
digest food. However, if the concentrations of acid in the stomach are too high, problems can occur. Pain, swelling,
inflammation and bleeding in the stomach’s lining can cause a condition commonly called acid indigestion. One solution to the
problem is to take a medication that contains an antacid – a mild base to neutralize the acid. The typical bases found in
common antacids are as follows: Alka-Seltzer (sodium hydrogen carbonate); Tums (calcium carbonate); Rolaids (calcium
carbonate); Maalox (magnesium hydroxide, aluminum hydroxide); milk of magnesia (magnesium hydroxide).
Title – be clear, specific and include more detail than you probably think you should.
Problem – Are all antacids equally effective?
Hypothesis – an if…then…because statement.
Materials – list all items used.
Procedure – step by step, alpha or numeric list, of what you did. Passive past tense. Special note: Think about
how many trials you want to complete for each test.
Observations – Tables & Graphs
Conclusion – restate the hypothesis and indicate whether it was correct or not. Be definitive.
Discussion – Answer the following questions and discuss anything of interest in the lab.
1.
2.
3.
4.
5.
6.
7.
8.
Which antacid tablet would you consider taking if you had an acid stomach problem? Explain.
Would you want an antacid to dissolve in your stomach instantly or over a period of time? Explain.
Contrast and compare liquid medicines to solid medicines.
Compare the neutralizing ability per gram of each antacid. Calculate the number of drops of acid that would be
neutralized by 1g of each antacid.
Determine the price of antacids per tablet, per gram or per recommended usage. Analyze and report on the cost value
of various brands of antacids.
Complete 3 different word equations, skeleton equations, and balanced chemical equations to represent 3 different
antacid reactions completed.
Are there any changes you would make to this lab if you did it again?
What is the most important thing you learned from completing this lab?
Lab Report Marking Scheme
Criteria
Knowledge
Title & Problem / Lab
Technique / Conclusion
Observations
Inquiry
Hypothesis / Materials /
Procedure
Application
Discussion / Evaluation
Questions
Communication
Explanation



Level
Clear, concise direction is given to the lab through problem & title.
Safe and competent skills are demonstrated throughout the lab.
Conclusion is thorough, accurate, logical.
Thorough, high quality, quantitative and qualitative observations. Tables and graphs are used
effectively to display data collected.
0
0
0
0
1
1
1
2
2
2
2
4
3
3
3
6
4
4
4
8



Clear, concise direction is given to the lab through hypothesis.
Materials list is appropriate and complete.
An elegantly designed set of procedures has been created.
0
0
0
1
1
2
2
2
4
3
3
6
4
4
8

Insightful examination of results. The use of knowledge and skills to make connections within
and between various contexts.
0
3
6
9
12

Spelling, grammar, scientific terminology, presentation, organization and completeness.
0
2
4
6
8

Level 4 – Excellent
Level 3 – Good
Level 1 – Limited
Level 0 – Incomplete
Level 2 – Satisfactory
Total
/60