Mr. BuchmanScience 7 Green House

Name ______Group ______Date ______

Review Sheet: Experimental Design and Scientific Method

Experimental Design

A. Scientific Method (Remember with “QHEIC” or “Quickly Heather Eats Ice Cream Rapidly”)

  1. Question – 1st step of Scientific Method – Be able to write a question that can be explored with an experiment
  2. Hypothesis – Be able to write in If-then-because format
  3. Experiment – Be able to design and conduct experiments
  4. Interpret Data – Be able to design and interpret charts, tables, and graphs
  5. Conclusion – Make a conclusion based on your hypothesis and the results of your experiment
  6. Repeat – a good experiment is repeated

B. Sources of Error: Be able to identify sources of error and evaluate your hypothesis based on experimental results

C. Key Vocabulary

  1. Independent Variable = Manipulated Variable = the variable you purposely change (remember with “IM purposely changing”)
  2. Dependent Variable = Responding Variable = the factor that may change as a result of the manipulated variable (remember with “the DR is expected”)
  3. Control Group = the Control = the setup with ‘normal’ conditions; conditions are NOT being changed; this group is used for comparison
  4. Constants = conditions that are kept the same in the experimental and control group so you have a controlled experiment

The Bouncing Ball Experiment

A student is interested in designing an experiment to see what ball will bounce the highest when dropped. Write a hypothesis that could be tested with an experiment.

Example:

Question: Which ball will bounce the highest when dropped?

Hypothesis: If______

______

______

Data

Type of ball:______

Perform 6 trials and measure using your meter stick

TrialHeight in cm

1

2

3

4

5

6

Mr. BuchmanScience 7 Green House

Name ______Group ______Date ______

Question and Hypothesis Worksheet

A student is interested in designing several experiments to test the factors that effect how quickly an Alka-Seltzer tablet dissolves in water (solution rate). For each question, write a hypothesis that could be tested with an experiment. Be sure each hypothesis is in the proper “If…then…because…” format. See example below.

Example:

Question: What effect does stirring have on solution rate?

Hypothesis: If the water is stirred, then the tablet will dissolve faster because stirring increases solution rate.

1. Question: What effect does the water temperature have on solution rate?

Hypothesis: ______

______

2. Question: What effect does crushing the tablet have on solution rate?

Hypothesis: ______

______

3. Question: What effect does adding soda to the water have on solution rate?

Hypothesis: ______

______

The next few questions are about factors effecting plant growth. Write a hypothesis for each question using the proper “If…then…because…” format. See example above.

4. Question: What effect does amount of light have on plant growth?

Hypothesis: ______

______

5. Question: What effect does amount of water have on plant growth?

Hypothesis: ______

______

6. Question: What effect does using plant food (Miracle Grow) have on plant growth?

Hypothesis: ______

______

Experimental Design Exercise

Choose one of the factors that effect how quickly an Alka-Seltzer tablet dissolves in water (solution rate). You will now follow the scientific method to determine if your hypothesis is correct. Use this sheet to plan your experiment and collect your data.

Question: Write the question you are trying to answer (see Question and Hypothesis Worksheet).

______

______

Hypothesis: Write your hypothesis using the proper “If…then…because…” format (See Question and Hypothesis Worksheet).

______

______

Experiment: Plan your experiment by following the steps below.

What is your manipulated variable (AKA independent variable AKA what you are testing)? ______

What is your responding variable (AKA dependent variable AKA what you are expecting will change)? ______

What variables must be kept constant for this to be a controlled experiment?

______

List ALL materials you will need to perform your experiment.

______

______

______

______

List the steps you will follow to perform your experiment. Don’t forget about the control group, and don’t forget to repeat the experiment!

1. ______

2. ______

3. ______

4. ______

5. ______

6. ______

Collect your data here – Complete the data table during your experiment.

Experimental Condition

/

Time to dissolve

/

Observations

Interpret Data: What does your data show? Be specific and descriptive.

______

______

______

______

Conclusion: Based on your experiment, is your hypothesis true? If it is true, restate your hypothesis below, if not true then revise your hypothesis below.

______

______

______

______

Do you want to try another experiment? If so, describe what you would like to do in the space below.

Bollinger - 1