Identify a chemical change mentioned in the book that occurs more quickly.
baking (rusting of iron with a salt catalyst)
How is it possible that water is a by-product of burning cellulose?
The cellulose contains the elements hydrogen and oxygen. H and O.
When water freezes we know that the volume increases. Explain how the volume can increase but no new material has been created.
the molecules have just spread apart from one another
True or False? A change in color can indicate that a chemical change has occurred.
True
Identify a slow chemical change mentioned in the book.
the rusting of iron
True or False? If matter looks different, it has definitely undergone a chemical change.
False
How do chemical changes create new substances?
breaking chemical bonds and creating new ones
True or False? In a physical change, new matter is always created.
False
Fill in the blank. Matter can neither be _______________ nor destroyed.
created
Fill in the blank: A chemical _____________________ is a specific example of one or more chemical changes.
reaction
How can you extract salt from water after it has been dissolved?
Allow the water to evaporate.
You are working with a certain material. It looks different than when you first started working with it. Has it definitely undergone a chemical change? Yes or no? Explain.
No - various explanations
Fill in the blank: A physical change is a change in size, _____________, or state of matter.
shape
What is a catalyst?
something that speeds up a chemical reaction
If a piece of wood had a mass of 10g, what would the mass of the carbon dioxide, water vapor, and ash be after the fire?
10g
Fill in the blank. The mass of matter before a chemical change must ____________ the mass afterwards.
equal
A change in the size, shape or state of matter with no new material being formed. Physical or chemical change?
physical change
How are ice and water different?
The motion and arrangement of the molecules are different.
How are ice and water the same if they are in two different states of matter?
They are the same chemical formula - H2O.
Name two forms of energy given off in a chemical change.
heat and light
When might it appear that matter has been lost?
when a gas is produced
True or False? Dissolving is a physical change.
True
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