Tutorial for Using Science Process Skills

How to Introduce Science Process Skills Using Experiments from “201 Awesome, Magical, Bizarre & Incredible Experiments.”

Very Important

The exploratory experiments in “201 Awesome, Magical, Bizarre & Incredible Experiments”  should be viewed as a type of research. Thus, the experiments provide hands-on experiences that demonstrate science facts.

The purpose of each experiment identifies the objective of the experiment.

For example, the objective of Experiment #83 Not at the Same Time is to demonstrate that objects submerged in water push or displace the water. This is an important science concept and one needed to understand the Water Displacement Method for measuring the volume of objects as well as understanding buoyancy in later investigations.

83  Not at the Same Time

Purpose  To observe that two pieces of matter cannot occupy the same place at the same time.

Materials
( Read through experiments and decide if other materials can be used. Suggestions are provided for the following material list.) 

• 9-ounce (270-ml) clear, plastic glass (any transparent cylinder-shaped container)
• tap water
• masking tape (wax marker or anything that will mark on the container used)
• 6 equal size marbles (objects that will fit into the container used)

Procedure
1. Fill the glass one-half full with tap water.   [Estimate amount of water needed to fill the glass one-half full.]
2. Mark the water level by placing a piece of tape on the glass. [Identifying water level; Developing fine-motor skills by marking water level.]

3. Tilt the glass and allow one marble at a time to slide through the water to the bottom of the glass.

Tip: As each marble is added, set the glass upright and decide if the water level changed. Kids might make predictions about how high they think the water level will rise when all six marbles are added.

4. With all six marbles added, set the glass upright and notice any change in the water level. [Observing and comparing]

Results:  The water level is higher with the marbles in the glass.

Why? Water and marbles are both examples of matter. Two pieces of matter cannot occupy the same space at the same time. When the marbles are dropped into the glass, the water is pushed out of the way by the marbles. The rise in the water level is equal to the volume of the six marbles.

Background Information for Enrichment

The volume of an object is how much space the object takes up; A graduate cylinder measures the volume of liquids in millimeters; Water displacement is a method of measuring the volume of solids.

Enrichment -1

Volume by Water Displacement

Purpose: To demonstrate the manner in which the volume of objects by the Water Displacement Method.

Materials

graduate cylinder
tap water
4-marbles of equal size

Procedure

1. Fill a graduated cylinder with 4 mL of water. Record this volume as the volume without marbles in a data table, such as the one show. [An example table is shown.]

2. Add two marbles to the graduate cylinder by tilting the cylinder slightly and allowing one marble at a time to roll down the side, through the water to the bottom of the cylinder.
3. Observe the new water level in the cylinder. Record this water level in the data chart. [The diagram shows the water level rising to 6mL. In the data table, 6mL is recorded as the water level with 2 marbles.
4. The amount of water pushed aside (displaced) by the marbles is the difference between the water level without marbles and the water level with 2 marbles.  The math is shown in the data table. [Keep the 2 marbles in the graduate for the next step.]

5. Use the graduate with 2 marbles from step 4. Add two marbles to the graduate, making a total of 4 marbles in the graduate cylinder.

6. Observe the new water level in the cylinder. Record this water level in the data chart. [Notice that 4mL was used for calculating the total rise in the water level with four marbles.]

7. Use the data chart to complete the following prediction.

Prediction: If a total of six marbles are added to the graduate cylinder, I predict the water will rise to _??______ in the graduated cylinder.

Experiment to test the prediction: Describe how you can perform an experiment to test your prediction. [The procedure used to measure the amount the water level rose with 2 marbles or 4 marbles can be used to test the hypothesis.]

Inference: Create a graph for predicting the level the water will rise to if you have a given number of marbles of equal size to the ones used in this experiment.

Note: The more data collected, the more reliable a graph is for predicting points between plotted data points or extrapolated points. 

Summary

• Water and marbles are both examples of matter. Two pieces of matter cannot occupy the same space at the same time.
• When the marbles are dropped into the glass, the water is pushed out of the way by the marbles.
• The marbles displace water, meaning the marbles push the water out of their way.
• The displaced water takes up space, thus in a container displaced water causes the water level to rise.
• The rise in the water level is equal to the volume of the marbles in the graduate cylinder. 
  

Real World Application

Have you noticed that water in a bathtub rises when you get into the water? This is because your body displaces the water in the tub.

The Greek mathematician, scientist and inventor Archimedes (c.287-212 B.C.) is said to have observed the water rising when he stepped into a bathtub of water. No doubt he had witnessed this before, but it was one of those aha! moments when Archimedes “connected the dots” and realized that the rise in water level is equal to the volume of the submerged object. The story goes that Archimedes needed to know the volume of the king’s crown so he could decide if it was made of pure gold. It is said that Archimedes was so excited that he left his bath and ran through the streets to the palace to tell the king he knew how to test his crown. The problem is that in his hurry, Archimedes did not dress and was running through the streets naked screaming  EUREKA!!! 

For more information about the importance of Archimedes discovery and how it helped him test the king’s crown, see Buoyancy,  on Homeschool World, the official web-site of Practical Homeschooling Magazine.

More information and experiments about Archimedes the scientists as well as other scientists can be  found in “Scientists Through the Ages.”

How to read a graduate cylinder and to use it to measure volume by Water Displacement.