Chemical Reactions

In a ___________change, a substance changes into a different substance.

• Physical
• Chemical

Which is the only way to be sure a chemical change has occurred? 

• Creation of a new substance
• An unexpected color change
• A temperature change
• The formation of a precipitate

Mrs. Young fills a balloon with helium and places it in a hot room. The helium atoms would most likely...

• Spread far apart
• Remain close together
• Lock in place
• Slow down, turning into a liquid

Keara has a new duck pond at her house. When winter comes the water will freeze. What is happening to the water molecules when this happens? 

• They are increasing in speed
• The are increasing in size
• The are bouncing off each other
• The are slowing down and creating a pattern

In which of these are particles moving the FASTEST? 

• Solid
• Liquid
• Gas
• Impossible to tell

Which of these has correctly ordered particle speed from fastest to slowest? 

• Solid - Liquid - Gas
• Gas - Liquid - Solid
• Liquid - Solid - Gas
• Gas - Solid - liquid

A change in a substance's STATE is an example of: 

• Chemical Change
• Physical Change

An gel ice pack getting cold after you put it in the freezer for an hour.

• Chemical Change
• Physical Change

Which of the following IS a physical change?

• Getting a haircut
• Rusty metal
• sour milk
• A compound

A burning match is an example of a: 

• Chemical Change
• Physical Change