# Lesson 1: Invisible Matter

## Activities

### Activity 1: Discovering that Matter Exists at an Invisible Level

Materials: 250-ml beaker (kit), dynamometer (kit), funnel (kit)*, pan, plastic milk jug, pot holder or oven mitt, safety goggles (kit), watch or timer
In this activity, you will boil water, pour it into an empty milk jug, seal the cap, and observe what happens. CAUTION: This activity requires handling boiling water. Be sure to wear safety goggles and handle the pot or beaker with a pot holder or oven mitt. Ask for a parent's assistance as needed.

First assemble your materials. You will need a pan, an empty milk jug with a lid, a 250-ml beaker (kit), a dynamometer (kit), a pot holder or oven mitt, safety goggles (kit), and a watch or timer. You may also need a funnel to make it easier to pour the boiling water into the container.
Procedure:
1. In a pan, heat approximately 200 ml (about 1 cup) of water until it boils. Be sure to observe what is happening with the water and think about the questions found at the top of the activity page.
2. On the activity page, sketch the empty milk jug.
3. After the water reaches the boiling point, use a pot holder or oven mitt to carefully pour the water into the empty milk jug.
4. Tightly cap the top of the container and then weigh the container and its contents. Record the mass on the activity page.
5. Set a timer for 5 minutes. When the timer goes off, observe what happens to the container and sketch what you see on the activity sheet.
6. Repeat Step 5 three more times (at 10, 15, and 20 minutes).
7. Record the mass of the container and its contents after 20 minutes. (HINT: Keep in mind that the water has transitioned from a liquid to a gas. How might that influence the weight you observe?)
8. Answer the questions at the bottom of the activity page and discuss your results with a parent. (The "Liquid and Gas Particles" image may help you answer the questions.)
Liquid and Gas Particles
Student Activity Page
In this activity, your child will pour boiling water into an empty milk jug, seal it, and observe and sketch what happens. CAUTION: This activity requires that your child handle boiling water. Encourage him to wear safety goggles and handle the pan with a pot holder or oven mitt. Provide assistance as needed.

Your child did not need to formally answer the questions at the top of the activity page — they were more questions to think about as he observed the water boiling — but you may want to discuss the answers with him at the end of the lesson:

As the water heats, what is happening to the water particles?
Answer: Though this is a concept that will be addressed later, it gives the students a good point of reference for future lessons within the unit. As heat (energy) is added to the water, the particles of water become energized. This increased amount of energy causes the water molecules to become excited and move more.

What is happening between the particles?
Answer: Bonds between molecules of water start breaking, releasing the water molecules as water vapor (a gas). These bonds will break as long as the energy level in the container is high enough. The energy from the water is also transferred to the air in the container, exciting the air molecules.

Note: The container will expand at first because of the increased particle movement of the water vapor. Your child should find little or no difference between the mass of the container at minute 0 and minute 20.

Be sure to check your student's answers to the questions found at the bottom of the activity sheet:
• What is happening to the milk jug and why? (The milk jug with the hot liquid should initially expand. After a while, the liquid and the gases in the milk jug will cool down and the container will contract. It will either return to its original shape or it will contract to a size even smaller than the original.)
• What is making the container do this? (The jug is expanding because particles of water [water vapor] are highly energized. Because they are energized by the heat, they are moving around quickly. More and more water vapor is being created, meaning that the volume of the particles is increasing. Also, the energy in the water vapor energizes the air in the container. As the water cools, the milk jug will contract.)
• What is the difference between the water at this time versus the water when you initially poured it into the container? (As the water cools down, its volume changes.)
• What change is happening to the water to make this event occur? (The amount of energy present. More energy produces more water vapor. As the energy dissipates, the water vapor returns to a liquid state.)

### Activity 2: Vocabulary

Materials: scissors
In this activity you will review some of the vocabulary that will be important for this unit. On the first "Vocabulary" page, create an illustration for each vocabulary term.

You should use ideas from Activity 1 to create your illustrations. For example, "matter" covers a lot of possibilities, but you can draw an image that represents water, the container that held the water, or even the heat source. Make sure that you understand what the term represents in as many contexts as possible. Cut out the cards, separating each word from its illustration, and set the cards aside.

Next, read over the words and definitions on the second "Vocabulary" page. Cut out the cards from this page, separating each word from its definition.

Use the two sets of cards to help you study the vocabulary words. You can do a Memory-type game or just try to match the definitions or illustrations to the words they describe. (Refer to the "Things to Know" section at the beginning of the lesson if you need to confirm definitions.) Your goal is to be able to recite the correct definition for each vocabulary word.
Student Activity Page
Student Activity Page
Your child should be able to cite the definition provided with a reasonable degree of comprehension and produce a drawing that reflects the same degree of understanding of the vocabulary term. Ideally some of the illustrations should refer to ideas from Activity 1. Comprehension should not be limited to the context of the activity or a specific item. Your child should be able to transfer this knowledge into a variety of contexts. You can help your child review using some of the follow-up questions at the end of the lesson.