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You are here: Home / Science Projects / Earth Science / Hypothesis: A Science Process Skill

Hypothesis: A Science Process Skill

January 25, 2021 By Janice VanCleave

A Hypothesis is a Well Thoughtout Prediction.Girl Thinking

Yes, asking groups of kids to guess what will happen can be fun. But, expecting a hypothesis for every experiment defeats the purpose for this science process skill.  A hypothesis relys on observations that have been previously made. Hypothesis are often called “educated” guesses. Please don’t require kids to give a hypothesis unless it can be based on previous knowledge.  In other words, a hypothesis must be based on schema, which is previously learned information.

Using an Exploratory Experiment to provide needed schema for a hypothesis. 

Research is any method used to learn more about a topic. Reading books, magazines as well as online sources and everyday observations of the world around you are good research methods. I suggest that research include exploratory experiments, such as those found in the science book shown. The following exploratory experiment was taken from , “201 Awesome, Magical, Bizarre & Incredible Experiments.” My intention in writing this and other experiment books was to provide fun experiments requiring around the house materials or materials easily found locally. These are exploratory experiments.

FYI:  My books are sold on Amazon as well as other online books suppliers. If you sell my books contact me and I will add a link to your website.

Book Jacket for 201 Awesome, Magical , Bizarre & Incredible Experiments

Facts: Provide information that kids may not be familiar with before introducing the experiment.

  • Pressure is the force pressing against a surface.
  • Gas molecules move in a straight line until they collide with each other or their container. When colliding, the gas molecules, much like balls striking a wall changes direction and continues moving. Unlike a ball, each gas molecule collides, changes direction and continue at the same speed as before its collision.

 Exploratory Experiment #141 Increasing

Problem: How does temperature affect air pressure?
Materials:
empty glass soda bottle (any glass bottle with a small mouth)
9-inch (23-cm) round balloon

Procedure
1. Place the open soda bottle in the freezer for 15 or more minutes. You want the air in the bottle to get cold.
2. Remove the bottle from the freezer. You can sit the bottle in an ice chest with ice. Make sure the chest is closed. You want the air inside to be cold.
3. Immediately stretch the opening of the balloon over the mouth of the bottle.
4. Stand the bottle at room temperature.
5. Observe and record any changes in the balloon for 5 minutes.
Results: The balloon partially inflates.
Analysis of Results:
Kids age 5 and above have a lot of schema about different topics, but they may not have the skills to retrieve it. It is kinda lot connecting the dots. Developing science process skills helps develops thinking patterns, thus helps develop creative thinking. My point is to help kids retrieve knowledge they already know with simple questions. While kids have their brains turned on and their schema reved up new information can be added. Learning is adding information to existing schema.
Use questions such as the following when discussing this experiment.
1.
Which is colder, the air in the freezer or the air in this room? Air in the freezer is colder than air at room temperature.
2.
Which has more energy, warm or cold air? Warm things have more energy, thus warm air has more energy.
3. Which moves faster, things with more or less energy? Things with more energy moves faster.
4. Which hits harder, a fast moving ball or a slow moving ball? Fast moving balls hit harder than slow moving balls.
Conclusion: Use these terms to explain why the balloon partially inflated: energy, temperature, inflate, pressure
Depending on age and ability, the conclusion should be something like this:
The balloon partially inflated because the cold air inside the bottle warmed. When warmer the air molecules moved faster and hit the inside of the balloon with more pressure.
FYI: Since gas molecules do not lose energy when colliding, the balloon will remain partially inflated at room temperature.
While not discussed in this experiment, the reason an open bottle was placed in the freezer was to fill the bottle with more air. The air molecules in the bottle would cool and take up less space, thus more cold air could fill the bottle. As the bottle warmed the excess air molecules added more pressure inside the balloon, thus partially inflating.

Something More

Now that kids are engaged –have their schema turned on– introduce a problem related to the previous exploratory experiment.

Problem Which takes up more space, cold air or warm air?
Hypothesis: Base your hypothesis on the results of the previous experiment.
Experiment: Volume of Cold Air vs Hot Air
Materials
2-glass empty soda bottles
two 9-inch (23-cm) round balloon
marker

Procedure:
1. Stand two identical open glass bottles at room temperature for 5 or more minutes. This allows the air inside both bottles to be at the same temperature.
2. With the marker, label one ballon C and the other W.
3. Stretch the opening of a balloon over the mouth of one of the bottles.

4. Observe and record the appearance of the balloon over the bottle.

5. Place the open bottle and the bottle with the balloon in a freezer for 15 or more minutes. Note: You can sit the bottles in an ice chest with ice. Make sure both bottles are equally cooled and the chest is closed.  Again, it is important for the air surrounding the bottles to be cold.

6. Remove both bottles, and immediately stretch the remaining balloon over the mouth of the open bottle.
7. Observe and record any changes in the two balloons covering the bottles.
Results:  
Analysis of Results:
Conclusion 
Briefly describe the purpose of this investigation and your hypothesis. Explain whether your experimental results did or did not support your hypothesis.
If it did not support your hypothesis, give reasons why and if possible suggest a follow up investigation. This all depends on the age and ability of person writing it.

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Filed Under: Earth Science, Science Projects Tagged With: air pressure, crystals, energy, exploratory experiment, gas molecules, hypothesis, inflate, pressure, schema, temperature

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