THE SCIENTIFIC METHOD

Experiment 1: Serious Sandwiches
Dr. Farquart wants to make her home-town a nicer place to live. She has created a new sauce that she predicts will reduce the production of body gas associated with eating sandwiches from the local cafe. She recruits 100 customers with a history of gas problems. She has 50 of them (group A) eat sandwiches with the new sauce. The other 50 (group B) eat sandwiches with sauce that looks just like the new sauce but is really only a mixture of mayonnaise and food coloring. Both groups were told that they were eating the sauce that would reduce gas production. Two hours after eating the sandwiches, 30 customers in group A reported having fewer gas problems and 8 customers in group B reported having fewer gas problems.

1. Which group represents the control group?

2. What is the independent variable?

3. What is the dependent variable?

4. What should Dr. Farquart’s conclusion be?

5. Why do you think 8 people in group B reported feeling better?

Experiment 2: Slimotosis
Rafael notices that his 3 pet turtles are suffering from “Slimotosis” which occurs when the shell develops a nasty slime and gives off a horrible odor. His friend, Ariel, tells him that rubbing seaweed on the shell is the perfect cure, while Aaron says that drinking kelp water will be a better cure. Rafael decides to test these cures by rubbing one turtle with seaweed for 1 week and having a second turtle drink kelp water. The third turtle is Explore not treated with either cure. After a week of treatment, the slime is gone from the turtle’s shell that drank the kelp water.
1. What was the initial observation?

2. What is the independent variable?

3. What is the dependent variable?

4. What should Rafael’s conclusion be?

Experiment 3: Muscle Cream
Leah was told that a certain muscle cream was the newest and best thing on the market. It claims to double a person’s muscle mass when used as part of a workout. Interested in this product, she buys the special muscle cream and recruits her friends, Samuel and Gideon, to help her out with an experiment. Leah develops a weight- lifting program for Samuel and Gideon. She meets with them once every day for a period of two weeks and records their results. Before each session Samuel applies the muscle cream to his arms and back, while Gideon applies regular lotion to his arms and back.
Weight Lifted Samuel Gideon
Initial 18 Kilograms 5 Kilograms
After 1 Week 24 Kilograms 9 Kilograms
After 2 Weeks 33 Kilograms 17 Kilograms

1. Which person is in the control group?

2. What is the independent variable?

3. What is the dependent variable?

4. What should Leah’s conclusion be?

Experiment 4: Microwave Miracle
Lee thinks that fish that eat food exposed to microwaves will become smarter and would be able to swim through a maze faster. He decides to perform an experiment by placing fish food in a microwave for 20 seconds. He has the fish swim through a maze and records the time it takes for each one to make it to the end. He feeds the special food to 10 fish and gives regular food to 10 others. After 1 week, he has the fish swim through the maze again and records the times for each.

1. What was Lee’s hypothesis?

2. Which fish are in the control group?

3. What is the independent variable?

4. What is the dependent variable?

5. Look at the results in the charts. What should Lee’s conclusion be?

Reading
Read the following section. Once you have completed the reading answer the questions below.
Holt McDougal Chemistry Chapter 2 Section 1 pages 27-29

1. What is the difference between accidental discoveries and scientific investigations?

2. What is the difference between qualitative and quantitative data?

3. Why is a scientific experiment limited to a single system?

4. Explain the difference between an educated guess and a scientific hypothesis.

5. What are controls and variables in a scientific experiment?

6. In science, what does the term theory mean?

7. How are models related to theories and hypotheses?

Explain