Matter is anything that has weight and takes up space.

No. Matter never just vanishes. When it seems to disappear it is just changing from one form to another. If it turns into a gas you can't see it with your naked eye. All matter is conserved, it just changes forms.

If a pot of water is left to boil on the stove, some of the water in the pot seems to disappear. Where does the water go?

When water is heated it changes form from liquid to gas. The gas then escapes into the air.

What does “conservation of matter” mean?

The phrase “conservation of matter” describes how the amount of matter stays the same, even if it changes form.

When the team mix 25 grams of sugar into 150 grams of water, the sugar seems to disappear! Where does it go?

The sugar dissolves into the water. It is still there, it simply changes into a form we can't see.

What evidence tells us that the sugar is still there, even though we can’t see it?

The sugar water weights 175 grams which is the same as all the sugar (25g) plus all the water (150g). This is evidence that the sugar is still there even though we can’t see it.

When Dr. Jeff boils the sugar water, what happens?

As the water is heated it changes forms from liquid to gas. The sugar is left behind as a solid, providing us with evidence that it was in there the whole time.

During the fire snake investigation, what caused the snake to be so much larger than the ingredients it came from (sugar and baking soda)?

When the sugar and baking soda were heated, a chemical reaction caused the ingredients to release gases that formed bubbles. Those bubbles expanded and made the snake look much larger than the original amount of ingredients.

Why did the fire snake weigh a little bit less than the ingredients it came from?

When Zoe weighs the ingredients (sugar and baking soda), it weighs 25 grams in total. When she weighs the “snake” it weighs 23 grams. This is because some carbon dioxide gas produced during the chemical reaction escapes into the air.

When dry ice appears to be smoking, what is actually happening?

The “smoke” coming from dry ice is actually carbon dioxide gas, which is turning from a solid into a gas. (Dry ice, or solid carbon dioxide, changes directly from a solid to a gas without becoming a liquid first.)

Would the weight of the flask and dry ice be the same before and after the dry ice disappears if the bottle was not sealed with the balloon?

No. If the bottle were not sealed by the balloon, the weight before and after would not be the same because the gas would escape into the air. In this case it would weigh less.

Why does the weight recorded on the scale go down as the candle burns?

When candle wax burns, it is changing into gases that are released into the air. As that gas escapes, it is no longer part of the candle so the scale doesn't account for it.

Conservation of Matter

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What you will learn from this videoWhat you will learn

The amount of matter is conserved when a substance changes form.
When a substance dissolves it doesn’t vanish, it simply changes form.
When something burns up it turns into gases that you can’t see.

Discussion Questions
- Before Video
  What is matter?ANSWER
  - Matter is anything that has weight and takes up space.
  Can matter vanish?ANSWER
  - No. Matter never just vanishes. When it seems to disappear it is just changing from one form to another. If it turns into a gas you can't see it with your naked eye. All matter is conserved, it just changes forms.
  If a pot of water is left to boil on the stove, some of the water in the pot seems to disappear. Where does the water go?ANSWER
  - When water is heated it changes form from liquid to gas. The gas then escapes into the air.
  What does “conservation of matter” mean?ANSWER
  - The phrase “conservation of matter” describes how the amount of matter stays the same, even if it changes form.
- After Video
  When the team mix 25 grams of sugar into 150 grams of water, the sugar seems to disappear! Where does it go?ANSWER
  - The sugar dissolves into the water. It is still there, it simply changes into a form we can't see.
  What evidence tells us that the sugar is still there, even though we can’t see it?ANSWER
  - The sugar water weights 175 grams which is the same as all the sugar (25g) plus all the water (150g). This is evidence that the sugar is still there even though we can’t see it.
  When Dr. Jeff boils the sugar water, what happens?ANSWER
  - As the water is heated it changes forms from liquid to gas. The sugar is left behind as a solid, providing us with evidence that it was in there the whole time.
  During the fire snake investigation, what caused the snake to be so much larger than the ingredients it came from (sugar and baking soda)?ANSWER
  - When the sugar and baking soda were heated, a chemical reaction caused the ingredients to release gases that formed bubbles. Those bubbles expanded and made the snake look much larger than the original amount of ingredients.
  Why did the fire snake weigh a little bit less than the ingredients it came from?ANSWER
  - When Zoe weighs the ingredients (sugar and baking soda), it weighs 25 grams in total. When she weighs the “snake” it weighs 23 grams. This is because some carbon dioxide gas produced during the chemical reaction escapes into the air.
  When dry ice appears to be smoking, what is actually happening?ANSWER
  - The “smoke” coming from dry ice is actually carbon dioxide gas, which is turning from a solid into a gas. (Dry ice, or solid carbon dioxide, changes directly from a solid to a gas without becoming a liquid first.)
  Would the weight of the flask and dry ice be the same before and after the dry ice disappears if the bottle was not sealed with the balloon?ANSWER
  - No. If the bottle were not sealed by the balloon, the weight before and after would not be the same because the gas would escape into the air. In this case it would weigh less.
  Why does the weight recorded on the scale go down as the candle burns?ANSWER
  - When candle wax burns, it is changing into gases that are released into the air. As that gas escapes, it is no longer part of the candle so the scale doesn't account for it.
Vocabulary
- Matter DEFINE
- Law of Conservation of Matter DEFINE
- Dissolve DEFINE
- Gram DEFINE
- Dry Ice DEFINE
- Conserve DEFINE
Reading Material
DIY Activity Guide
Lesson Plan
Lesson Plan
Teacher Guide
Assessment
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